Soil acidity is an important factor affecting crop productivity in the tropics. The soil of the Vietnamese Mekong Delta has high acidity, deficient levels of exchangeable bases, and low fertility. This study aimed to evaluate soil amendments’ role in improving soil fertility, soil acidity, and pomelo yield cultivated in raised beds. The field trial was carried out in Hau Giang province consecutively over 3 years from 2018 to 2020. Fours treatments were used, namely, control, biochar (5 ton ha⁻¹ year⁻¹), lime (2 ton ha⁻¹ year⁻¹), and compost (5 ton ha⁻¹ year⁻¹). All treatments applied the same amount of NPK fertilizers at rates of 400 kg N, 300 kg P₂O₅, and 400 kg K₂O ha⁻¹ year⁻¹. Physicochemical properties of the topsoil (0–20 cm) and subsoil (20–40 cm), and fruit yield were investigated. The results showed that biochar or compost application increased soil pH, soil organic matter (SOM), and exchangeable cations, and decreased soil bulk density (BD), improving soil fertility and fruit yield in the raised beds. Applications of biochar or compost resulted in about 1.5-fold higher fruit yield than that of chemical fertilizer alone. The average profit increased to USD 1,672 ha^–1 after applying biochar and compost in the three-year experiments. Biochar and compost amendments have a positive effect on reducing soil acidity and soil BD, elevating SOM, and supplying available Ca²⁺ and Mg²⁺, improving soil fertility, enhancing fruit yield, and increasing profit.