Crocus keltepensis (Iridaceae) is described as a new endemic species from Kocaeli province in north-western Turkey. Diagnostic morphological characters, a full description, and detailed illustrations are given herein. Crocus keltepensis is distributed in a restricted area in the highest part of the Samanli Mountains. According to its morphological features, it belongs to C. sect. Nudiscapus set Biflori. It shows morphological similarities with C. pulchricolor, which belongs to the same series. However, these two species are separated from each other by flower color, corm tunics, leaf and seed macromoiphological characteristics.