A process for preparing a catalytic cracking catalyst, which process comprises: a molecular sieve is introduced into a gas-phase ultra-stabilization reactor, the molecular sieve is moved without the conveying of carrier gas from a molecular sieve inlet of the gas-phase ultra-stabilization reactor to a molecular sieve outlet of the gas-phase ultra-stabilization reactor, and the molecular sieve is contacted and reacted with a gaseous SiCl4 in the gas-phase ultra-stabilization reactor, the molecular sieve resulting from the contacting and the reacting is optionally washed, then mixed with a matrix and water into slurry, and shaped into particles.