Four globular, convoluted, hollow species of brown algal genus Colpomenia (Endlicher) Derbès et Solier were collected from different coastal areas of Karachi (Pakistan) at northern Arabian Sea and taxonomically investigated in detail. They included one new species, C. hasanainii Aisha et Shameel, which differed from all the existing species. Most of these species are reported and taxonomically described for the first time from the coast of Pakistan.