The extract of the aerial parts of Fumaria bastardii Bor. afforded 12 alkaloids belonging to the skeletally six different groups of the isoquinoline alkaloids. In this publication, the isolation and identification of protopine (1), corydaldine (2), oxyhydrastinine (3), (-)-fumaritine (4), (+)-fumariline (5), (-)-O-methylfumarophycine (12), (+)-bicuculline (10), $(-)-{eta}-hydrastine$ (7), (-)-corlumine (11), (+)-tetrahydropalmatine (8), (-)-stylopine (6), and (+)-juziphine (9) are described. Their structures have been determined by using extensive spectroscopic techniques. This is the first report of the occurrence of these alkaloids in Fumaria bastardii of Turkish origin.