diff --git a/x-pack/plugins/observability_solution/entity_manager/server/lib/entities/errors/entity_definition_id_too_long_error.ts b/x-pack/plugins/observability_solution/entity_manager/server/lib/entities/errors/entity_definition_id_invalid.ts
similarity index 75%
rename from x-pack/plugins/observability_solution/entity_manager/server/lib/entities/errors/entity_definition_id_too_long_error.ts
rename to x-pack/plugins/observability_solution/entity_manager/server/lib/entities/errors/entity_definition_id_invalid.ts
index fb78f237bee37..4d6110f661aa0 100644
--- a/x-pack/plugins/observability_solution/entity_manager/server/lib/entities/errors/entity_definition_id_too_long_error.ts
+++ b/x-pack/plugins/observability_solution/entity_manager/server/lib/entities/errors/entity_definition_id_invalid.ts
@@ -5,9 +5,9 @@
  * 2.0.
  */
 
-export class EntityDefinitionIdTooLong extends Error {
+export class EntityDefinitionIdInvalid extends Error {
   constructor(message: string) {
     super(message);
-    this.name = 'EntityDefinitionIdTooLong';
+    this.name = 'EntityDefinitionIdInvalid';
   }
 }
diff --git a/x-pack/plugins/observability_solution/entity_manager/server/lib/entities/transform/validate_transform_ids.test.ts b/x-pack/plugins/observability_solution/entity_manager/server/lib/entities/transform/validate_transform_ids.test.ts
index 9a8d23b16c973..9320cd1324b75 100644
--- a/x-pack/plugins/observability_solution/entity_manager/server/lib/entities/transform/validate_transform_ids.test.ts
+++ b/x-pack/plugins/observability_solution/entity_manager/server/lib/entities/transform/validate_transform_ids.test.ts
@@ -5,7 +5,7 @@
  * 2.0.
  */
 
-import { EntityDefinitionIdTooLong } from '../errors/entity_definition_id_too_long_error';
+import { EntityDefinitionIdInvalid } from '../errors/entity_definition_id_invalid';
 import { entityDefinition } from '../helpers/fixtures/entity_definition';
 import { validateDefinitionCanCreateValidTransformIds } from './validate_transform_ids';
 
@@ -20,7 +20,25 @@ describe('validateDefinitionCanCreateValidTransformIds(definition)', () => {
       'a-really-really-really-really-really-really-really-really-really-really-long-id';
 
     expect(() => {
-      validateDefinitionCanCreateValidTransformIds(entityDefinition);
-    }).toThrow(EntityDefinitionIdTooLong);
+      validateDefinitionCanCreateValidTransformIds(entityDefinitionWithLongID);
+    }).toThrow(EntityDefinitionIdInvalid);
+  });
+
+  it('should throw an error for a definition ID which contains invalid characters', () => {
+    const entityDefinitionWithDots = entityDefinition;
+    entityDefinitionWithDots.id = 'dots.are.not.allowed';
+
+    expect(() => {
+      validateDefinitionCanCreateValidTransformIds(entityDefinitionWithDots);
+    }).toThrow(EntityDefinitionIdInvalid);
+  });
+
+  it('should throw an error for a definition ID which ends with dash or underscore', () => {
+    const entityDefinitionEndingInUnderscore = entityDefinition;
+    entityDefinitionEndingInUnderscore.id = 'looking-good-but_';
+
+    expect(() => {
+      validateDefinitionCanCreateValidTransformIds(entityDefinitionEndingInUnderscore);
+    }).toThrow(EntityDefinitionIdInvalid);
   });
 });
diff --git a/x-pack/plugins/observability_solution/entity_manager/server/lib/entities/transform/validate_transform_ids.ts b/x-pack/plugins/observability_solution/entity_manager/server/lib/entities/transform/validate_transform_ids.ts
index 320505134dd9b..baf010f2dc2df 100644
--- a/x-pack/plugins/observability_solution/entity_manager/server/lib/entities/transform/validate_transform_ids.ts
+++ b/x-pack/plugins/observability_solution/entity_manager/server/lib/entities/transform/validate_transform_ids.ts
@@ -5,13 +5,13 @@
  * 2.0.
  */
 
-const TRANSFORM_ID_MAX_LENGTH = 64;
-
 import { EntityDefinition } from '@kbn/entities-schema';
-import { EntityDefinitionIdTooLong } from '../errors/entity_definition_id_too_long_error';
+import { EntityDefinitionIdInvalid } from '../errors/entity_definition_id_invalid';
 import { generateHistoryTransformId } from './generate_history_transform_id';
 import { generateLatestTransformId } from './generate_latest_transform_id';
 
+const TRANSFORM_ID_MAX_LENGTH = 64;
+
 export function validateDefinitionCanCreateValidTransformIds(definition: EntityDefinition) {
   const historyTransformId = generateHistoryTransformId(definition);
   const latestTransformId = generateLatestTransformId(definition);
@@ -20,10 +20,17 @@ export function validateDefinitionCanCreateValidTransformIds(definition: EntityD
     TRANSFORM_ID_MAX_LENGTH - Math.max(historyTransformId.length, latestTransformId.length);
 
   if (spareChars < 0) {
-    throw new EntityDefinitionIdTooLong(
+    throw new EntityDefinitionIdInvalid(
       `Entity definition ID is too long (max = ${
         definition.id.length + spareChars
       }); the resulting transform ID will be invalid`
     );
   }
+
+  const transformIdRegex = /^[a-z0-9][a-z0-9_-]*[a-z0-9]$/;
+  if (!transformIdRegex.test(definition.id)) {
+    throw new EntityDefinitionIdInvalid(
+      'Entity definition ID must contain only lowercase alphanumeric characters (a-z and 0-9), hyphens, and underscores. It must also start and end with alphanumeric characters.'
+    );
+  }
 }