The concentrations of Cd, Pb, Cu and Zn in scalp hair of 100 khat chewers and 100 normal subjects were determined by anodic stripping voltammetry. Hair samples were brought into solution by using a mixture of nitric and perchloric acids. The efficiency of the decomposition, and the accuracy and precision of the proposed procedure was studied using a human hair standard. The results indicated that the hair of Yemeni khat users had significantly higher concentrations of cadmium, lead and copper than did normal controls but slightly less amount of zinc. The possible connection of these elements with the etiology of disease is discussed. The results confirm the need for reducing the amount of khat currently digested and the immediate improvements of “khat sessions” ventilation.