i have completed my MBA in Marketing and i m join mechanical field for marketing. Is it good for my future?

There is no problem for you to joining 'mechanical field for marketing' at all.you must not leave your core subject i.e.,MARKETING.you keep your job profile same and can enter different types of fields.

mansi , you have already completed your MBA meaning you must now be well equipped with business skills. combined with that pursuing career in marketing in mechanical field will provide you with a blend of both business and technical skills which will prove advantageous for your future.

Yes you are on the right track. Now try ot learn the tricks of the trade as much as possible from your job in the initial days. Keep evaluationg yourself and have your own targets to keep you motivated.

A student of Management can survive and leave its marks everywhere, so don't worry about anything just do with full potentialities.