Indoor culture and pot experiments were conducted to investigate the effects of nitrogen and phosphorus fertilizer combined with different dosages (0, 0.5, 1.0, and 2.0 g/kg) of mineral conditioner on pH, contents of available phosphorus, calcium, magnesium and silicon in soil as well as on lettuce yields and absorption of nitrogen, phosphorus and potassium by lettuce. The results of indoor culture experiments showed that when the dosage of mineral conditioner was 1.0 g/kg and 2.0 g/kg, soil pH increased from 5.02 to 5.31 and 5.61, thus, enhanced soil anti-acidification ability. Meanwhile, the fixed rate of phosphate fertilizer applied to soil was delayed, the available phosphorus contents increased by 21.49% and 24.17% in 15d and 22.09% and 23.84% in 22d, respectively. The results of pot experiments showed that when the dosage of mineral conditioner was 0.5-2.0 g/kg, soil mineral nutrients were effectively increased, lettuce yields were increased by 10.47%–33.33%, and the uptakes of nitrogen, phosphorus and potassium increased by 14.69% -44.26%, 15.28%-52.89% and 16.28%-42.43%, respectively. So, it is an effective way to apply mineral conditioner for ameliorating soil acidity, replenishing soil nutrients, and increasing crop nutrition absorption and yield.