A new species of the gekkonid genus Goniurosaurus is described from Cat Ba Island, Hai Phong, northern Vietnam. G. catbaensis sp. n. is, by its gracile body and limbs, the thin, posteriorly protracted nuchal loop, the three (or four) thin immaculate dorsal body bands between limb insertions, without dark spotting and with dark, narrow border surrounding the body bands, the lack of postrostral (internasal) scales, the presence of a greatly enlarged row of supraorbital tubercles, the outer surface of the upper eyelid being composed of granular scales of about the same size of those on top of head and with a longish row of 6–9 enlarged tubercles, granular body scales, with 8–11 granular scales surrounding the dorsal tubercles, deep axillary pockets, claws being sheathed by four scales, and 16–21 precloacal pores. The new taxon is known only from Cat Ba Island and is the eleventh Goniurosaurus species known and the fourth known species from Vietnam. We provide first data on its natural history and a key to the currently recognized Goniurosaurus species.