diff --git a/azurerm/internal/services/postgres/resource_arm_postgresql_server.go b/azurerm/internal/services/postgres/resource_arm_postgresql_server.go
index 8cc850d40b9c..216f44df3876 100644
--- a/azurerm/internal/services/postgres/resource_arm_postgresql_server.go
+++ b/azurerm/internal/services/postgres/resource_arm_postgresql_server.go
@@ -23,8 +23,8 @@ import (
 )
 
 func ValidatePSQLServerName(i interface{}, k string) (_ []string, errors []error) {
-	if m, regexErrs := validate.RegExHelper(i, k, `^[0-9a-z]{2}[-0-9a-z]{0,60}[0-9a-z]$`); !m {
-		errors = append(regexErrs, fmt.Errorf("%q can contain only lowercase letters, numbers, and '-', but can't start or end with '-' or have more than 63 characters.", k))
+	if m, regexErrs := validate.RegExHelper(i, k, `^[0-9a-z][-0-9a-z]{1,61}[0-9a-z]$`); !m {
+		errors = append(regexErrs, fmt.Errorf("%q can contain only lowercase letters, numbers, and '-', but can't start or end with '-'. And must be at least 3 characters and at most 63 characters", k))
 	}
 
 	return nil, errors
diff --git a/azurerm/internal/services/postgres/validation_test.go b/azurerm/internal/services/postgres/validation_test.go
new file mode 100644
index 000000000000..f465936116c7
--- /dev/null
+++ b/azurerm/internal/services/postgres/validation_test.go
@@ -0,0 +1,68 @@
+package postgres
+
+import (
+	"testing"
+)
+
+func TestValidatePSQLServerName(t *testing.T) {
+	testData := []struct {
+		input    string
+		expected bool
+	}{
+		{
+			// empty
+			input:    "",
+			expected: false,
+		},
+		{
+			// basic example
+			input:    "ab-c",
+			expected: true,
+		},
+		{
+			// can't contain upper case letter
+			input:    "AbcD",
+			expected: false,
+		},
+		{
+			// can't start with a hyphen
+			input:    "-abc",
+			expected: false,
+		},
+		{
+			// can't contain underscore
+			input:    "ab_c",
+			expected: false,
+		},
+		{
+			// can't end with hyphen
+			input:    "abc-",
+			expected: false,
+		},
+		{
+			// can not short than 3 characters
+			input:    "ab",
+			expected: false,
+		},
+		{
+			// 63 chars
+			input:    "abcdefghijklmnopqrstuvwxyzabcdefabcdefghijklmnopqrstuvwxyzabcde",
+			expected: true,
+		},
+		{
+			// 64 chars
+			input:    "abcdefghijklmnopqrstuvwxyzabcdefabcdefghijklmnopqrstuvwxyzabcdef",
+			expected: false,
+		},
+	}
+
+	for _, v := range testData {
+		t.Logf("[DEBUG] Testing %q..", v.input)
+
+		_, errors := ValidatePSQLServerName(v.input, "name")
+		actual := len(errors) == 0
+		if v.expected != actual {
+			t.Fatalf("Expected %t but got %t", v.expected, actual)
+		}
+	}
+}