Rats are one of the non-halal animals to be consumed for the Muslim community. Lately the issue of rat meat adulteration is common, so it will disserve the Moeslim consumer. The Liquid Chromatography-Mass Spectrometry (LC-MS) method is a good method that can be used to detect amino acids. The purpose of this study was to find the amino acid constituents that could be a marker for detection rat meat using LC-MS in combination with PCA chemometric (Principle Component Analysis). Identification of amino acid of rat meat is hydrolyzed with strong acid HCl followed by heating using oven at 110ºC to be separated in LC and detected with MS. The results obtained are chromatogram profile and LC-MS spectrum then identified the composition for each of amino acid constituents. The result of the analysis showed that amino acid composition of black and white rats have similarity when viewed from PCA. Analysis using PCA showed amino acid rat meat with beef, chicken, goat can be differentiated and separated into 4 different quadrants.