In this study, we report the rediscovery of Primula cooperi Balf.f. whose existence was seen as a mystery until now. It was first collected in the year 1913 from North Sikkim by Roland Edgar Cooper. Since its first discovery, it has not been rediscovered again. It was declared extinct as its type locality had been repeatedly surveyed without success. Based on our recent rediscovery, characteristics of the species is updated supported by photographs and measurements. The latest IUCN Red List categorised its conservation status as Critically Endangered. Lastly, a phylogenetic analysis revealed P. cooperi as a member of P. sect. Proliferae of the sub-genus Aleuritia with P. prenantha being its closest sister taxon. Morphologically, it has close affinities with P. brachystoma and P. polonensis.