Phrynobatrachus njiomock is a species of frogs in the family Phrynobatrachidae. It is endemic to Cameroon and is only known from Mount Oku where it occurs near Lake Oku. It has not been observed after 2010 and might already be extinct. The specific name njiomock means eleventh in Oku language and refers to the name Phrynobatrachus sp. 11 that Jean-Louis Amiet used in 1978 to refer to a specimen collected near Lake Oku. Common name Lake Oku puddle frog has been proposed for this species.