diff --git a/types/sequelize/index.d.ts b/types/sequelize/index.d.ts
index b15fe2790c..ec4831a16d 100644
--- a/types/sequelize/index.d.ts
+++ b/types/sequelize/index.d.ts
@@ -19,6 +19,7 @@
 //                 Duy Truong <https://github.com/truongkhanhduy95>
 //                 Emmanuel Gautier <https://github.com/emmanuelgautier>
 //                 Dan Rumney <https://github.com/dancrumb>
+//                 Kan Yueh Chen <https://github.com/lalayueh>
 // Definitions: https://github.com/DefinitelyTyped/DefinitelyTyped
 // TypeScript Version: 3.2
 
@@ -36,6 +37,8 @@ import * as _ from "lodash";
 import Promise = require("bluebird");
 import * as cls from "continuation-local-storage"
 
+type Omit<T, K extends keyof T> = Pick<T, Exclude<keyof T, K>>
+
 declare namespace sequelize {
 
     //
@@ -3939,9 +3942,18 @@ declare namespace sequelize {
          * Search for a single instance by its primary key. This applies LIMIT 1, so the listener will
          * always be called with a single instance.
          */
-        findById<TCustomAttributes>(identifier?: number | string | Buffer, options?: FindOptions<TAttributes & TCustomAttributes>): Promise<TInstance | null>;
-        findByPrimary<TCustomAttributes>(identifier?: number | string | Buffer, options?: FindOptions<TAttributes & TCustomAttributes>): Promise<TInstance | null>;
-        findByPk<TCustomAttributes>(identifier?: number | string | Buffer, options?: FindOptions<TAttributes & TCustomAttributes>): Promise<TInstance | null>;
+        findById<TCustomAttributes>(
+          identifier?: number | string | Buffer,
+          options?: Omit<FindOptions<TAttributes & TCustomAttributes>, 'where'>,
+        ): Promise<TInstance | null>;
+        findByPrimary<TCustomAttributes>(
+          identifier?: number | string | Buffer,
+          options?: Omit<FindOptions<TAttributes & TCustomAttributes>, 'where'>,
+        ): Promise<TInstance | null>;
+        findByPk<TCustomAttributes>(
+          identifier?: number | string | Buffer,
+          options?: Omit<FindOptions<TAttributes & TCustomAttributes>, 'where'>,
+        ): Promise<TInstance | null>;
 
         /**
          * Search for a single instance. This applies LIMIT 1, so the listener will always be called with a single
diff --git a/types/sequelize/sequelize-tests.ts b/types/sequelize/sequelize-tests.ts
index ceb98dc773..a085357637 100644
--- a/types/sequelize/sequelize-tests.ts
+++ b/types/sequelize/sequelize-tests.ts
@@ -1008,17 +1008,81 @@ User.findAll( { where: { emails: { $overlap: ["me@mail.com", "you@mail.com"] } }
 var options: Sequelize.AnyFindOptions = { where: { $and: Sequelize.where( Sequelize.fn( 'char_length', Sequelize.col('username') ), 4 ) } };
 User.findAll( options );
 
-User.findById( 'a string' );
-User.findById( 42 );
-User.findById( Buffer.from('a buffer') );
+User.findById( 1 );
+User.findById( 1, { attributes : ['id'] } );
+User.findById( 1, { logging : function(  ) { } } );
+User.findById( 1, { transaction : t } );
+User.findById( 1, { include : [User] } );
+User.findById( 1, { include : [{ model : User }] });
+User.findById( 1, { include : [{ model : User, as : 'ToDo' }] });
+User.findById( 1, { include : [User, { model : User, as : 'ToDo' }] });
+User.findById( 'id' );
+User.findById( 'id', { attributes : ['id'] } );
+User.findById( 'id', { logging : function(  ) { } } );
+User.findById( 'id', { transaction : t } );
+User.findById( 'id', { include : [User] } );
+User.findById( 'id', { include : [{ model : User }] });
+User.findById( 'id', { include : [{ model : User, as : 'ToDo' }] });
+User.findById( 'id', { include : [User, { model : User, as : 'ToDo' }] });
+User.findById( Buffer.from('id') );
+User.findById( Buffer.from('id'), { attributes : ['id'] } );
+User.findById( Buffer.from('id'), { logging : function(  ) { } } );
+User.findById( Buffer.from('id'), { transaction : t } );
+User.findById( Buffer.from('id'), { include : [User] } );
+User.findById( Buffer.from('id'), { include : [{ model : User }] });
+User.findById( Buffer.from('id'), { include : [{ model : User, as : 'ToDo' }] });
+User.findById( Buffer.from('id'), { include : [User, { model : User, as : 'ToDo' }] });
 
-User.findByPrimary( 'a string' );
-User.findByPrimary( 42 );
-User.findByPrimary( Buffer.from('a buffer') );
+User.findByPrimary( 1 );
+User.findByPrimary( 1, { attributes : ['id'] } );
+User.findByPrimary( 1, { logging : function(  ) { } } );
+User.findByPrimary( 1, { transaction : t } );
+User.findByPrimary( 1, { include : [User] } );
+User.findByPrimary( 1, { include : [{ model : User }] });
+User.findByPrimary( 1, { include : [{ model : User, as : 'ToDo' }] });
+User.findByPrimary( 1, { include : [User, { model : User, as : 'ToDo' }] });
+User.findByPrimary( 'id' );
+User.findByPrimary( 'id', { attributes : ['id'] } );
+User.findByPrimary( 'id', { logging : function(  ) { } } );
+User.findByPrimary( 'id', { transaction : t } );
+User.findByPrimary( 'id', { include : [User] } );
+User.findByPrimary( 'id', { include : [{ model : User }] });
+User.findByPrimary( 'id', { include : [{ model : User, as : 'ToDo' }] });
+User.findByPrimary( 'id', { include : [User, { model : User, as : 'ToDo' }] });
+User.findByPrimary( Buffer.from('id') );
+User.findByPrimary( Buffer.from('id'), { attributes : ['id'] } );
+User.findByPrimary( Buffer.from('id'), { logging : function(  ) { } } );
+User.findByPrimary( Buffer.from('id'), { transaction : t } );
+User.findByPrimary( Buffer.from('id'), { include : [User] } );
+User.findByPrimary( Buffer.from('id'), { include : [{ model : User }] });
+User.findByPrimary( Buffer.from('id'), { include : [{ model : User, as : 'ToDo' }] });
+User.findByPrimary( Buffer.from('id'), { include : [User, { model : User, as : 'ToDo' }] });
+
+User.findByPk( 1 );
+User.findByPk( 1, { attributes : ['id'] } );
+User.findByPk( 1, { logging : function(  ) { } } );
+User.findByPk( 1, { transaction : t } );
+User.findByPk( 1, { include : [User] } );
+User.findByPk( 1, { include : [{ model : User }] });
+User.findByPk( 1, { include : [{ model : User, as : 'ToDo' }] });
+User.findByPk( 1, { include : [User, { model : User, as : 'ToDo' }] });
+User.findByPk( 'id' );
+User.findByPk( 'id', { attributes : ['id'] } );
+User.findByPk( 'id', { logging : function(  ) { } } );
+User.findByPk( 'id', { transaction : t } );
+User.findByPk( 'id', { include : [User] } );
+User.findByPk( 'id', { include : [{ model : User }] });
+User.findByPk( 'id', { include : [{ model : User, as : 'ToDo' }] });
+User.findByPk( 'id', { include : [User, { model : User, as : 'ToDo' }] });
+User.findByPk( Buffer.from('id') );
+User.findByPk( Buffer.from('id'), { attributes : ['id'] } );
+User.findByPk( Buffer.from('id'), { logging : function(  ) { } } );
+User.findByPk( Buffer.from('id'), { transaction : t } );
+User.findByPk( Buffer.from('id'), { include : [User] } );
+User.findByPk( Buffer.from('id'), { include : [{ model : User }] });
+User.findByPk( Buffer.from('id'), { include : [{ model : User, as : 'ToDo' }] });
+User.findByPk( Buffer.from('id'), { include : [User, { model : User, as : 'ToDo' }] });
 
-User.findByPk( 'a string' );
-User.findByPk( 42 );
-User.findByPk( Buffer.from('a buffer') );
 
 User.findOne( { where : { username : 'foo' } } );
 User.findOne( { where : { id : 1 }, attributes : ['id', ['username', 'name']] } );