Empirical standard weight equations, Length-weight and length-length relationships were estimated for Barbus pergamonensis, Capoeta bergamae and Ladigesocypris irideus, three endemic cyprinid species of Turkey which are still not widely studied. To the best knowledge of the authors, empirical standard weight equations for three species and L-W parameters for L. irideus are given for the first time. In this study, length and weight data for B. pergamonensis, C. bergamae and L. irideus were collected throughout the watercourses of Mugla Province and were used to develop species-specific Ws equations. The results were for B. pergamonensis (total length (TL) range: 6-22 cm) log^Ws= - 5.713 + 3.718 log^TL - 0.166 (log10TL)2; for C. bergamae (TL range: 8-29 cm) log10Ws= - 5.224 + 3.311 log10TL - 0.083 (log10TL)2; for L. irideus (TL range: 6-10 cm) log10Ws= - 13.298 + 12.116 log10TL - 2.471 (log10TL)2. This study reported also new maximum TLs for the three species together with species- specific length-weight and length-length equations.