1. The conversion of cyclohexane, cyclohexene, and 1,4-cyclohexadiene on the Na forms of zeolites of types A, X, Y, and L, as well as chabazite, erionite, and mordenite, in a batch microreactor has been investigated. 2. The conversion products of cyclohexene are cyclohexane and methylcyclopentarne. The greatest activity in this process is displayed by mordenite. 3. 1,4-Cyclohexadiene is converted into 1,3-cyclohexadiene, cyclohexene, and benzene, the latter forming in dehydrogenation and disproportionation reactions. Zeolite NaY displays the greatest dehydrogenating activity among the zeolites investigated.