Acacia is a large group of plant species that are widely distributed in temperate and arid parts of the world [1]. Most of the common applications of plants belonging to Acacia species are for the production of gum and the wide use of bark tannins in the tanning industry. Acacia rigidula is a species that grows in southern part of Texas, USA. The leaf extract of this plant is widely used in several weight-loss and body-building products in the US market with no published data on its biological effects. Further, with little confirmation, limited chemical investigation on the A. rigidula leaves have reported the presence of more than 40 bioactive alkaloids and amines belonging to several classes [2]. Our investigation is focused on confirming the presence of the alkaloid constituents using sensitive LC-MS and GC-MS analysis of the extracts. The study further focuses on isolation and characterization of unique chemical markers that can be used to develop quantitative analytical methods for plant identification.