A report was conducted to assess the genetic diversity among Simmental Cross cattle in West Sumatra using microsatellite DNA markers. process has taken place with the Simmental Purebred. In view of the advantages possessed by the Simmental Cross cattle and the evaluation of the genetic diversity results, a number of subpopulations in this study can be considered as the initial (base) populace for the Simmental Cross cattle breeding programs in West Sumatra, Indonesia. [PO]) and the Simmental Purebred sires. The superior properties of the Simmental Cross Salirasib cattle are its good level of adaptability to tropical climates and strong ability to grow. As a result, the farmers in West Sumatra prefer using the Simmental Purebred semen (Siregar et al., 1999) for their cows when applying artificial insemination (AI) technology from Lembang Artificial Insemination Center (BIB Lembang) or Tuah Sakato Artificial Insemination Center (BIBD Tuah Sakato). In West Sumatra, artificial insemination has intensively used the Simmental Purebred semen for years resulting in an increased Simmental Combination cattle people in Western world Sumatra and provides produced cattle populations with improved morphological information set alongside the regional cattle (Agung et al., 2014). This sensation motivated the farmers and the neighborhood Government to create a mating plan for the Simmental Combination cattle in Western world Sumatra. The achievement of the mating program could be affected by many factors, including identifying the amount of the original (bottom) people to be able to generate offspring in keeping with the goals from the mating program. Recently, regional farmers and the neighborhood Government of Western world Sumatra have already been facing complications in determining the original (bottom) people for the mating program from the Simmental Combination cattle. This issue can be due to several elements including insufficiency of hereditary information about today’s status from the Simmental Combination cattle, having less studies about hereditary variety in Simmental Combination cattle, as well as the distribution from the Simmental Combination cattle in a big area of Western world Sumatra, Indonesia. Microsatellites are nearly ideal hereditary markers because they’re abundant, codominant, polymorphic highly, and are disseminate across the whole euchromatic area of the genome (Bennett, 2000). Microsatellites could be employed for estimating the hereditary length (Rehman and Khan, 2009), the partnership among livestock breeds (Maretto et al., 2012), as well as the hereditary variety (Mao et al., 2008). This research was conducted to review the hereditary variety in the Simmental Combination cattle in Western world Sumatra using microsatellite markers as technological evidence for the most recent status from the Simmental Combination cattle in Western world Sumatra and in addition grouping the Simmental Combination cattle people in Western world Sumatra you can use as the original (bottom) populace for breeding programs. MATERIALS AND METHODS Blood sampling and DNA collection Salirasib Blood samples were collected from herds owned privately and by artificial insemination centers. Genomic DNA was extracted using DNeasy Blood & Tissue Kit (Qiagen, Hilden, Germany). A total of 176 DNA samples were collected and classified into three groups, i.e. Simmental Purebred, Simmental Cross, and Ongole Grade (PO) cattle (Table 2). Blood samples of Simmental Cross cattle were obtained from West Sumatera provinces and (KAR) Farm in West Java, Indonesia. Blood samples of Simmental Purebred cattle were obtained from two locations, i.e. Lembang Artificial Insemination Center (BIB Lembang) in West Java and Tuah Sakato Artificial Insemination Center (BIBD Tuah Sakato) in West Sumatra, whereas the blood samples from Ongole Grade MAP2 (PO) cattle were obtained from the Research Center for Biotechnology (RC Salirasib Biotech.) Farm in West Java. Table 2 Summary statistic of the mean quantity of observed allele (Na), imply quantity of effective alleles (Ne), observed (Ho) and expected (He) heterozygosities observed in 11 cattle populations The sampling of the Simmental Cross cattle blood in West Sumatra in this study was divided into three areas based on the size of the Simmental cattle populace i.e. high populace (Limapuluh Kota), medium populace (Agam, Padang, Payakumbuh, Solok, Sawahlunto, and Tanah Datar), and low populace (Pariaman). The samples from Pariaman (an area with very low populace of Simmental cattle) was included in the analysis as a comparison study and also.