I am going to finish my engineering. Should I do MBA or should I work in a company first?

If you are very passionate and hard working, or MBA course is adding much value in your career growth, then you can opt for MBA. Or, you have completed your engineering, but your work or pay is not much what you are expecting, then you can opt for MBA. Otherwise you should join the company, alongsid

It depends on your preference. If you're the person who would like to get into a job and gain some practical experience by applying the knowledge you have got from your engineering, then absolutely go for a job. If you are not ready or not interested in doing a job right now and if you're interested

You should do a job first and get some experience. It will help you to get a good college in MBA and also understand concepts better.