diff --git a/charts/postgres-operator/crds/operatorconfigurations.yaml b/charts/postgres-operator/crds/operatorconfigurations.yaml
index e01a5f997..fb36340e2 100644
--- a/charts/postgres-operator/crds/operatorconfigurations.yaml
+++ b/charts/postgres-operator/crds/operatorconfigurations.yaml
@@ -66,6 +66,9 @@ spec:
                 nullable: true
                 items:
                   type: string
+              database_name_regexp:
+                type: string
+                default: "^[a-zA-Z_][a-zA-Z0-9_]*$"
               docker_image:
                 type: string
                 default: "ghcr.io/zalando/spilo-15:2.1-p9"
diff --git a/docs/reference/operator_parameters.md b/docs/reference/operator_parameters.md
index 198870d77..b1086b14b 100644
--- a/docs/reference/operator_parameters.md
+++ b/docs/reference/operator_parameters.md
@@ -177,6 +177,12 @@ Those are top-level keys, containing both leaf keys and groups.
   operator's own container, change the [operator deployment manually](https://github.com/zalando/postgres-operator/blob/master/manifests/postgres-operator.yaml#L20).
   The default is `false`.
 
+
+* **database_name_regexp**
+  By default the operator will follow the naming conventions for PostgreSQL. However,
+  the regexp can be modified to customize the validation.
+  The default is `^[a-zA-Z_][a-zA-Z0-9_]*$`.
+
 ## Postgres users
 
 Parameters describing Postgres users. In a CRD-configuration, they are grouped
diff --git a/manifests/configmap.yaml b/manifests/configmap.yaml
index e2fb21504..82923b64e 100644
--- a/manifests/configmap.yaml
+++ b/manifests/configmap.yaml
@@ -26,6 +26,7 @@ data:
   crd_categories: "all"
   # custom_service_annotations: "keyx:valuez,keya:valuea"
   # custom_pod_annotations: "keya:valuea,keyb:valueb"
+  # database_name_regexp: "^[a-zA-Z_][a-zA-Z0-9_]*$"
   db_hosted_zone: db.example.com
   debug_logging: "true"
   # default_cpu_limit: "1"
diff --git a/manifests/operatorconfiguration.crd.yaml b/manifests/operatorconfiguration.crd.yaml
index 8582c866a..5a0875d5c 100644
--- a/manifests/operatorconfiguration.crd.yaml
+++ b/manifests/operatorconfiguration.crd.yaml
@@ -64,6 +64,9 @@ spec:
                 nullable: true
                 items:
                   type: string
+              database_name_regexp:
+                type: string
+                default: "^[a-zA-Z_][a-zA-Z0-9_]*$"
               docker_image:
                 type: string
                 default: "ghcr.io/zalando/spilo-15:2.1-p9"
diff --git a/pkg/apis/acid.zalan.do/v1/operator_configuration_type.go b/pkg/apis/acid.zalan.do/v1/operator_configuration_type.go
index 4ff5ee81e..750b81475 100644
--- a/pkg/apis/acid.zalan.do/v1/operator_configuration_type.go
+++ b/pkg/apis/acid.zalan.do/v1/operator_configuration_type.go
@@ -3,10 +3,10 @@ package v1
 // Operator configuration CRD definition, please use snake_case for field names.
 
 import (
-	"github.com/zalando/postgres-operator/pkg/util/config"
-
 	"time"
 
+	"github.com/zalando/postgres-operator/pkg/util/config"
+
 	"github.com/zalando/postgres-operator/pkg/spec"
 	v1 "k8s.io/api/core/v1"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
@@ -102,6 +102,7 @@ type KubernetesMetaConfiguration struct {
 	PodManagementPolicy                      string              `json:"pod_management_policy,omitempty"`
 	EnableReadinessProbe                     bool                `json:"enable_readiness_probe,omitempty"`
 	EnableCrossNamespaceSecret               bool                `json:"enable_cross_namespace_secret,omitempty"`
+	DatabaseNameRegexp                       string              `json:"database_name_regexp" default:"^[a-zA-Z_][a-zA-Z0-9_]*$"`
 }
 
 // PostgresPodResourcesDefaults defines the spec of default resources
diff --git a/pkg/cluster/cluster.go b/pkg/cluster/cluster.go
index 590fe6564..80716d276 100644
--- a/pkg/cluster/cluster.go
+++ b/pkg/cluster/cluster.go
@@ -294,6 +294,10 @@ func (c *Cluster) Create() error {
 		c.eventRecorder.Eventf(c.GetReference(), v1.EventTypeNormal, "Services", "The service %q for role %s has been successfully created", util.NameFromMeta(service.ObjectMeta), role)
 	}
 
+	if err = c.readValidateDatabaseNameRegexp(c.OpConfig.DatabaseNameRegexp); err != nil {
+		return err
+	}
+
 	if err = c.initUsers(); err != nil {
 		return err
 	}
@@ -337,6 +341,7 @@ func (c *Cluster) Create() error {
 	// that feature explicitly
 	if !(c.databaseAccessDisabled() || c.getNumberOfInstances(&c.Spec) <= 0 || c.Spec.StandbyCluster != nil) {
 		c.logger.Infof("Create roles")
+
 		if err = c.createRoles(); err != nil {
 			return fmt.Errorf("could not create users: %v", err)
 		}
@@ -345,9 +350,11 @@ func (c *Cluster) Create() error {
 		if err = c.syncDatabases(); err != nil {
 			return fmt.Errorf("could not sync databases: %v", err)
 		}
+
 		if err = c.syncPreparedDatabases(); err != nil {
 			return fmt.Errorf("could not sync prepared databases: %v", err)
 		}
+
 		c.logger.Infof("databases have been successfully created")
 	}
 
diff --git a/pkg/cluster/cluster_test.go b/pkg/cluster/cluster_test.go
index 29272eac9..d93edd69c 100644
--- a/pkg/cluster/cluster_test.go
+++ b/pkg/cluster/cluster_test.go
@@ -46,6 +46,7 @@ var cl = New(
 			Resources: config.Resources{
 				DownscalerAnnotations: []string{"downscaler/*"},
 			},
+			DatabaseNameRegexp: "^[a-zA-Z_][a-zA-Z0-9_]*$",
 		},
 	},
 	k8sutil.NewMockKubernetesClient(),
diff --git a/pkg/cluster/database.go b/pkg/cluster/database.go
index 3ec36bb67..1099a124e 100644
--- a/pkg/cluster/database.go
+++ b/pkg/cluster/database.go
@@ -5,6 +5,7 @@ import (
 	"database/sql"
 	"fmt"
 	"net"
+	"regexp"
 	"strings"
 	"text/template"
 	"time"
@@ -415,6 +416,24 @@ func (c *Cluster) executeCreateDatabaseSchema(databaseName, schemaName, dbOwner
 		"creating database schema", "create database schema")
 }
 
+// readValidateDatabaseNameRegexp validates the regex expression. If the validation was
+// successful, it sets the global regex object variable for validation.
+func (c *Cluster) readValidateDatabaseNameRegexp(expr string) error {
+	if !(len(expr) > 0) {
+		return fmt.Errorf("The regex expression for the database name validation is not set")
+	}
+
+	regex, err := regexp.Compile(expr)
+	if err != nil {
+		return fmt.Errorf("The regex expression %q for the database name validation is not correct", expr)
+	}
+
+	databaseNameRegexp = regex
+	c.logger.Infof("regexp for database name/schema validation has been initialized")
+
+	return nil
+}
+
 func (c *Cluster) execCreateDatabaseSchema(databaseName, schemaName, dbOwner, schemaOwner, statement, doing, operation string) error {
 	if !c.databaseSchemaNameValid(schemaName) {
 		return nil
diff --git a/pkg/cluster/database_test.go b/pkg/cluster/database_test.go
new file mode 100644
index 000000000..9263da968
--- /dev/null
+++ b/pkg/cluster/database_test.go
@@ -0,0 +1,31 @@
+package cluster
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestReadValidateDatabaseNameRegexp(t *testing.T) {
+	tests := []struct {
+		name       string
+		expression string
+		wantErrMsg string
+	}{
+		{"default value", databaseNameRegexp.String(), ""},
+		{"null value", "", "validation is not set"},
+		{"wrong expression", "12(@3202@@!)#)$$%#$_!@@!_*%_@", "validation is not correct"},
+		{"correct expression", "^[a-z0-9]([-_a-z0-9]*[a-z0-9])?(\\.[a-z0-9]([-_a-z0-9]*[a-z0-9])?)*$", ""},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			err := cl.readValidateDatabaseNameRegexp(tt.expression)
+			if len(tt.wantErrMsg) > 0 {
+				assert.Containsf(t, err.Error(), tt.wantErrMsg, "expected error containing %q, got %s", tt.wantErrMsg, err)
+			} else {
+				assert.Nil(t, err)
+			}
+		})
+	}
+}
diff --git a/pkg/util/config/config.go b/pkg/util/config/config.go
index df1cf6bb8..54171f5a4 100644
--- a/pkg/util/config/config.go
+++ b/pkg/util/config/config.go
@@ -2,11 +2,10 @@ package config
 
 import (
 	"encoding/json"
+	"fmt"
 	"strings"
 	"time"
 
-	"fmt"
-
 	"github.com/zalando/postgres-operator/pkg/spec"
 	"github.com/zalando/postgres-operator/pkg/util/constants"
 	v1 "k8s.io/api/core/v1"
@@ -246,6 +245,7 @@ type Config struct {
 	PatroniAPICheckInterval                  time.Duration     `name:"patroni_api_check_interval" default:"1s"`
 	PatroniAPICheckTimeout                   time.Duration     `name:"patroni_api_check_timeout" default:"5s"`
 	EnablePatroniFailsafeMode                *bool             `name:"enable_patroni_failsafe_mode" default:"false"`
+	DatabaseNameRegexp                       string            `name:"database_name_regexp" default:"^[a-zA-Z_][a-zA-Z0-9_]*$"`
 }
 
 // MustMarshal marshals the config or panics