Random microsatellite amplify polymorphic DNA (RMAPD) is a new method of molecular marker. It can reveal genome DNA polymorphisms of organism only when random primer and microsatellite forward or reverse primer are combined together as a pair of primers by the PCR reaction system with Taq DNA polymerase, MgCl2, dNTPs and contemplate DNA. The core question of RMAPD is validity of the primers used. A lot of experiments of RMAPD in 69 Xinong Saanen dairy goats showed that RMAPD primers were effective. Comparison of RMAPD, microsatellite and RAPD markers demonstrated that RMAPD was different from each other in primers, amplification protocol and repetition. RMAPD is not equal to RAPD, but a extendable RAPD. Therefore, RMAPD is regarded as a new method of molecular marker. As it has many characteristics of DNA marker, RMAPD has a widest potential application in animal breeding and genetics, such as analysis of genetic structure and relationship and MAS.