If you are looking to play Hollow Knight on a portable device, you have legitimate options:
If you are searching for an official Hollow Knight PSP ISO or CSO file, it does not exist.
Hollow Knight was developed by Team Cherry and released in 2017, six years after the PlayStation Portable (PSP) was discontinued. The technical specifications of the PSP are not capable of running the official version of the game. The official game is available on: hollow knight psp iso updated
For the ultimate nostalgic form factor, the GPD Win 4 resembles a chunky PSP but runs Windows 11. You can install Hollow Knight from Steam or GOG. Again, no ISO needed.
Short of time travel or a miracle optimization engine, no. The PSP hardware is permanently capped. However, the PSP emulation community might one day create a wrapper that translates Hollow Knight’s Unity engine into PSP-compatible MIPS assembly. This is highly unlikely—even the Nintendo 64 and PS1 have trouble running post-2010 indie games. If you are looking to play Hollow Knight
That said, the “updated” part of your search keyword isn’t meaningless. The homebrew demake mentioned earlier (the two-room test) received a March 2026 update adding:
You can find it by searching “HK_Pocket v0.3” on GitHub. It’s not an ISO. It’s a .pbp file (PSP executable). And it’s charming—but it is not the full game. Short of time travel or a miracle optimization engine, no
For PPSSPP (PC/Mobile Emulator): This is the recommended way to play this port. The PSP hardware is nearly 20 years old and struggles with a game as complex as Hollow Knight. An emulator can overclock the virtual CPU to make the game run at a smoother framerate.
For Real PSP Hardware: Playing this on an actual PSP-1000, 2000, or 3000 requires a modded console (Custom Firmware).