Soil acidification will aggravate the magnesium(Mg)deficiency in soil and citrus trees，and the Mg fertilization is the main measure to solve the Mg deficiency in citrus orchards. Nowadays，Mg fertilizers with lower price and higher solubility such as magnesium sulfate(MgSO4)fertilizer are often used in agricultural production. But the hydrolysis of MgSO4 is strong and it is a fast-acting Mg fertilizer，the nutrient is easy to leach and difficult to meet the needs of citrus and other perennial crops. Therefore，further research is needed to determine which Mg fertilizer is more effective in citrus orchards. In this study，the effects of three commonly used Mg fertilizers，including MgSO4，magnesium carbonate(MgCO3)and magnesium oxide(MgO)，on acidic Mg deficient soils were evaluated with the main indexes of reducing soil acidity，replenishing soil and citrus tree Mg nutrient，and improving citrus yield and quality. The field experiment for two consecutive years showed that the soil exchangeable Mg content in the tillage layer(0-40 cm)of the no-Mg fertilization treatment(CK)decreased from 27.7 to 22.5mg/kg，while that of with Mg fertilizer treatment increased to 29.2-34.5 mg/kg，compared with the CK treatment，and the soil pH was extremely significantly and positively correlated with the exchangeable Mg content. Among them，the effect of MgCO3 on reducing soil acidity and increasing soil exchangeable Mg content was better than those of MgSO4 and MgO. In addition，the application of Mg fertilizer significantly increased the leaf Mg concentration and decreased the potassium(K)concentration making the leaf K/Mg ratio and calcium(Ca)/Mg ratio reasonable，among which MgCO3 application had the best effect. The application of three different Mg fertilizers to acidic Mg-deficient soils increased the fruit set and fruit yield of citrus，and the treatments of MgSO4，MgCO3 and MgO increased the yield by 5.7%，28.4% and 12.5%，respectively，compared with the CK treatment. Meanwhile，the fruit flavor quality was further improved by applying MgCO3 and MgO compared to the CK treatment. The soluble solids and vitamin C content of fruits increased by 8.41% and 1.46% on average in Mg fertilization treatments，respectively. In citrus orchards with acidic Mg deficient soils，MgCO3 was more effective in synergistically regulating acidity，supplementing Mg nutrient，increasing yield and improving fruit quality，followed by MgO and then MgSO4. These results could provide useful exploration and technical support for effective solution of Mg deficiency in citrus orchards with acidic Mg deficient soils.