Mr_No on 11 July 2014
This is the chronological order:
MGS3
MGS Portable Ops
MGS Peace Walker
MGS Ground Zeroes
MGS5 The Phantom Pain (hasn't been released yet)
MGS1
MGS2
MGS4
This is probably the most popular suggestion, because the series can get a bit confusing sometimes and you could get lost. Since The Phantom Pain hasn't been released yet, and I don't know if you plan on buying it, that game can be left for last.
