This study determined the carapace length (CL)-weight relationships of the fiveDecapoda species (Pachygrapsus marmoratus, Carcinus aestuarii, Liocarcinus depurator, Liocarcinus navigator, and Eriphia verrucosa) living in the Black Sea. The crab samples were obtained between 2010 and 2016 by SCUBA, trawl, trammel net, and dredges at six locations (Kastamonu, Sinop, Samsun, Ordu, Giresun, and Trabzon). Total carapace length (CL) and weight (W) of each individual were recorded with an accuracy of 0.01 cm and 0.01 g, respectively. During the sampling period, a total of 5932 crab individuals belonging to five species were collected and measured. The minimum and the maximum“b” values of the length-weight relationship among these five species were estimated as 2.442 (for L. navigator) and 3.007 (for P. marmoratus), respectively. Growth was found as isometric for P. marmoratus and C. aestuarii, and as negative allometric for L. depurator, L. navigator and E. verrucosa.