Catalytic cracking of triphenylethylene in the presence of a number of solid acid catalysts at 500-600A degrees C in a steam atmosphere at a contact time of 1-3 s has been studied. It has been shown that the main products of cracking are diphenylacetylene, 1,1-diphenylethylene, and stilbene. The influence of some factors on the yield and composition of cracking products has been investigated. Schemes for the formation mechanism of the main reaction products are presented.