The invention discloses a conversion technology for catalytic diesel. The conversion technology comprises the following steps that (1) mixed materials of catalytic cracking diesel and hydrogen enter ahydrogenation reactor for hydrofining reaction; (2) hydrofining reaction effluent directly enters a cracking reactor and is subjected to contact reaction with hydrocracking catalyst beds in the cracking reactor, wherein a hydrocracking reactor is filled with an upper hydrocracking catalyst bed and a lower hydrocracking catalyst bed in a grading manner, a catalyst of the upper bed takes W-Ni and/or Mo-Ni as an active metal component and takes a modified Y molecular sieve and/or alkali metal or alkaline earth metal modified aluminum oxide as a carrier, and a catalyst of the lower bed takes Mo-Co as an active metal component and takes the modified Y molecular sieve and carbon deposit aluminum oxide as a carrier; and (3) the hydrocracking reaction effluent obtained in the step (2) is subjected to separation and fractionation so as to obtain a naphtha component and a diesel component. According to the conversion technology, on the premise that the conversion rate of the catalytic diesel isbetter met, the hydrogenation saturation of a generated gasoline component is reduced, and the octane value of the gasoline component is increased.