Quaternary alkaloids of the following species of Papaveraceae were studied. From Hunnemannia fumariaefolia sweet cyclanoline, escholidine and alkaloid HF3 were isolated, from Papaver atlanticum ball magnoflorine, from P. caucasicum Marsch.-Bieb., P.dubium L. and P. litwinowii Fedde ex Bornm. aporheine methohydroxide, and from P. pseudo-orientale (Fedde) Medw. a new alkaloid, isothebaine methohydroxide were isolated. In P. confine Jord, magnoflorine was found and in two chemotypes of P, rhoeas L. β-stylopine, methohydroxide and aporheine methohydroxine could be proved.