Releasing free space in mdf file to OS We have a 120GB database. There was table with 60GB of data which is useless and we have truncated it. 

Now database size is 120GB with free space 60GB. The database will not grow up to 60GB in at least 3 months. So can we shrink the data file.

Am aware of fragmentation issue. I can rebuild my index since our's is not a 24*7 database. 

Please advice on shrinking MDF file
What exactly you are trying to achieve by shrinking the database? 
You should plan for the database growth and have reserved space for this growth.

So why don't you leave it as it is to have allocated space for new data coming to your DB.

It has been discussed so many times that you do not want to shrink your databases. Check this out and think twice before shrinking:

Stop Shrinking Your Database Files. Seriously. Now. By Brent Ozar