Abstract: Cyclic arsenic mercaptides (such as Ⅱ and Ⅲ) were synthesized as potential chemotherapeutic agent in the treatment of leukemia or tumour. Various dithiols and dichloroarsines were condensed without any solvent, to form the ring compounds of arsenic (Ⅱ and Ⅲ). Condensation of dithiols with arsenoxides could also give the desired products. Attempts to prepare the seven-membered cyclic mercaptides, by treating 1,4-butane dithiol with various dichloroarsines, were not, unsuccessful. The preparation of several aliphatic dithiols and dichloroarsines was also described. Some modifications of the processes had been made. Experimental chemotherapeutic results will be reported elsewhere.