Its a palette called Colodore, You can find it on lospec website.
It's kinda hard to work with, but really fun to do.
Is this the EGA palette? If not, it at least reminds me of that (but like, exceptional use of it, if so; that palette typically looks ugly, but this is some great, inventive color selection/placement).
Nice, pic. The colodore palette is actually a very good approximation of the palette used by the Commodore C64 computer.