The invention relates to an anti-basic nitrogen diesel oil yield increase catalysis cracking catalyst and a preparation method thereof. The catalyst comprises a cracking activity component, a mesoporous silicon-aluminum material, an adhesive and clay, wherein the cracking activity component comprises a first Y type molecular sieve and a second Y type molecular sieve, and contains or does not contain a third Y type molecular sieve, rare earth content in the first Y type molecular sieve is 8-23 wt% (calculated as rare earth oxide), iron content in the first Y type molecular sieve is 0.1-3.0 wt% (calculated as Fe2O3), copper content in the first Y type molecular sieve is 0-3.0 wt% (calculated as CuO), phosphorus content in the first Y type molecular sieve is 0-2.0 wt% (calculated as P2O5), sodium oxide content in the first Y type molecular sieve is 0.1-2.5 wt%, the second Y type molecular sieve is a magnesium-containing ultra-stable Y type molecular sieve, and the third Y type molecular sieve is a rare earth-containing DASY molecular sieve. The catalyst preparation method comprises: carrying out pulping on a cracking activity component, a mesoporous silicon-aluminum material, an adhesive and clay, and carrying out spray drying, washing, filtering and drying. With application of the catalyst in catalytic cracking of high basic nitrogen content hydrocarbon oil, high conversion rate and high diesel oil yield are provided.