Goniobranchus bombayanus is a species of colourful sea slug, a dorid nudibranch, a marine gastropod mollusc in the family Chromodorididae.
Goniobranchus bombayanus is a chromodorid nudibranch with a translucent white mantle with rounded purple spots and an orange submarginal band of coalescent spots. The centre of the back has a brownish hue and the surface is raised into tiny white papillae. The body reaches a length of 30 mm. It is very similar to Goniobranchus kitae.