Capparis spinosa L is one of the most commonly used Uigur traditional medicine for the treatment of rheumatism and gout. To explain this plant’s medicinal bioactivity, we studied the alkaloids from this plant and afforded 9 alkaloids. Their structures were elucidated by means of spectral analysis. They are Uracil(CS-1), Hypoxanthine(CS-2), Adenosine(CS-3), capparilosides A(CS-4), L-stachydrine(CS-5), Stachydrine methyl ester chloride(CS-6), Cadabicine (CS-7), CS-8 and CS-9. Hypoxanthine(CS-2) was isolated from this plant for the first time. Stachydrine methyl ester chloride(CS-6) was new natural product. CS-8 and CS-9 were new compounds who named as Capparispine and Cadabicine 26-O-β-D-glucoside hydrochloride, respectively. We employed in vitro test to screen out some substances which have inhibite-activity for lymphocyte proliferation. The results reveal that the cruel alkaloids can inhibite the proliferation of lymphocyte induced by LPS. On the base of in vitro test, the anti-inflammatory activity of cruel alkaloids was investigated in vivo. The results explained the cruel alkaloids have not anti-inflammatory activity.