Aim: The main aim of the study is to investigate the phytochemical screening of C. decapetala along with the content determination of different species of genus Caesalpinia with respect to their antidiabetic activity and identification of most bioactive species belonging to different origins. Methods: To achieve our goal different species of genus Caesalpinia collected from China and Pakistan were subjected to open column chromatography, High Pressure Liquid Chromatography (HPLC), antioxidant, and antidiabetic assays for evaluation. Results: From η-BuOH fraction of C. decapetala extract, eight compounds were isolated using open column chromatography and identified as apigenin-7-rhamnoside (1), 4-O-methylepisappanol (2), caesalpinol (3), daucosterol (4), astragalin (5), kaempferol (6), quercitrin (7), and naringin (8) using Nuclear Magnetic Resonance (NMR) spectroscopy. HPLC analysis of different species of genus Caesalpinia showed that the most active antidiabetic compound ‘quercitrin’ was present more in C. pulcherrima followed by decreasing order in C. sappan, C.decapetala, and C. bonduc. Conclusion: The results indicated that quercitrin is the most bioactive content and C. pulcherrima is most bioactive specie of China origin from genus Caesalpinia.