This research aims to identify the BMP-15 gene in Sumba Ongole (SO) cattle (Bos indicus) which were reared extensively in Sumba Island. This gene has been known for its function in regulating reproductive performance in cows. The blood sample was collected from 161 SO cattle. The first step was DNA isolation from blood and the second step was electrophoresis and extraction. It then continued with optimization of annealing temperature, amplification, and sequencing. The results of sequencing were analyzed using a software program, Basic Local Alignment Search Tool (BLAST). The annealing temperature optimization results obtained temperature of 58 °C was the proper temperature to amplify DNA. All samples studied with BMP-15 gene amplification gained results of 350 bp. Results of BLAST program analysis and Mega 6.01 program showed a close genetic relationship, characterized by the result sequence of BMP-15 of SO cattle possessing proximity to other ruminants, such as Bos taurus and Capra hircus breed. Based on this study, it could be concluded that the BMP-15 gene amplified successfully of 350 bp and has the adjacency of nucleotide sequence with the BMP 15 gene in some other types of ruminants.