The analysis of the alkaloid content of Corydalis claviculata has led to the isolation of thirty-one isoquinoline alkaloids, of which six are new. One is an aminoethylstilbene, crassifoline methine [2], one is an indanobenzazepine, (+)-norribsine [3], and four are cularines, (+)-corycularicine [4], oxocularicine [7], sauvagnine [8], and dihydrosauvagnine [9].