Finance is basically a specialization that you do in MBA. In MBA you can specialize in a number of domains. To name a few sales and marketing, finance, consulting, operations, general management, HR etc.

In your second year of MBA you have to select electives which will determine the domain you specialize in. There are also a number of certifications that people interested in the finance domain do like CFA, NCFM etc

MBA finance is a field which requires one to posses skills in Mathematics, economics and financial theory which is all covered in a great deal when you start pursuing MBA degree with specialisation in finance.

This helps you in going to the field where you will be managing all the financial decisions of company to make it earn profit as much as possible. Every firm needs an employee who can has done management course in finance and can handle the financial status of their company  in a better way.