Which specialisation in MBA is better for an engineering graduate?

project management or finance

If you are going to study an MBA you should know that it is a Master in Business Administration, it doesn't have specializations. The core courses in an MBA program cover various areas of business such as accounting, finance, marketing, human resources and operations in a manner most relevant to management analysis and strategy.

If you need another focus it is not an MBA, it is another thing. 

Depends on what your personal prefrence is and what line of business you currently are involved in, there is no market preference.

for example:

you like making money, focus on finance and cash management specialization.

you lile selling staff, focus on marketing specilazation.

I fully agree with the answers been added by EXPERTS...............Thanks.