A method of rapid and selective detection and purification of contracture-inducing insect toxins from Buthinae scorpion venoms is described in this paper. It consists of two main steps: the first one is specific as it uses immunoaffinity chromatography with antibodies against Androctonus australis Hector IT; the second, reverse phase high pressure liquid chromatography, allows the final separation of the different toxins present in each of the three venoms studied. Two, three and four insect toxins have been purified, respectively, from the venoms of Androctonus australis Hector, Buthus occitanus mardochei and Leiurus quinquestriatus quinquestriatus. This work demonstrates that, in Buthinae venoms, contracture-inducing insect toxins antigenically related to AaH IT, the first one purified, constitute the most important and, in some cases, the only toxins present.