How to Play GTA: San Andreas on PSP for Free - A Detailed Review
The PSP remains a legendary device. But San Andreas pushed the PS2 to its limits. Asking the PSP to run it is like asking a scooter to tow a boat. It can move, but barely.
Disclaimer: We do not condone piracy or any other form of copyright infringement. The methods outlined above are for educational purposes only. Make sure to respect the intellectual property rights of game developers.
There is no native way to download or play an official version of GTA: San Andreas on a PSP. Videos claiming to show the game running on the system are often April Fool's pranks or feature specialized remote-play setups. Unofficial Methods and Workarounds
The Short Answer: You cannot play the official GTA: San Andreas on a PSP for free (or even paid), because Rockstar Games never released San Andreas for the PSP.