In this study,the aim is to determine the best model forplantlength, dry stem. and dry leaf weightin different species of bittervetch by using non-linear growth models. In the study IFVE 3977-SEL 2802, HAT-1.4, 3977-SEL 2802 and Mardin Population bitter vetch species.were.used as materials. Bertalanffy, Logistic, and Gompertz models were used. At Ithe.erid of the study; the best models identiyingplantlength of bitter vetch Logistic in IFVE 3977-SEL 2802. species and Bertalanffy model in IFVE 3351-SEL2804, 11AT-14 and Mardin Population species: Dry stem weight was identified best with Logistic Model in IFVE 3977-SEL2802 add HAT-14-species, Bertalanffy model inIFVE 3351-SEL 2804 and. Gompertz model in Mardin population species. Dry leaf weight was identified best with Gompertz model in IFVE 3977-SEL 2802 and Mardin Population, Logistic model in IFVE 3351-SEL 2804 and-HAT 14 species.