Yes, there are some taxes and charges depending on the type of Mutual Fund you are redeeming(Equity Mutual Funds and Debt Mutual Funds).
1. Exit load
Exit load is like a penalty for withdrawing your investments too soon. Mutual Funds usually do not have lock-ins but they do charge you for very quick withdrawal of funds. Not all funds have it but it is fairly common in equity funds. Recently liquid mutual funds also have started levying it. Also, the length of time considered as too-soon is generally 1 year for equity funds (there are exceptions) but varies greatly for debt funds. For Liquid funds, it's 7 days.
It is only applicable when you sell your Mutual Fund units 'too soon'.
Equity funds: 1% of the total amount being withdrawn within 1 year of being invested is deducted. If the units are held for more than 1 year, then no exit load is applicable. This is the most general case. However there are funds with exit load extending beyond 1 year as well.
Debt funds: For Short Term Debt funds, it is usually nil; for Medium Term Debt funds it may be nil or have a very short applicable period e.g. a week to a month. For Long Term Debt funds it is usually 1% and the applicable period ranges from 6 months to an year. For liquid funds exit load of upto 0.007% will be applicable if withdrawn before 7 days. After 7 days there is no exit load.
The following is a snapshot of taxes. You can read about these in detail here.