Background: This study aimed to evaluate the effects of potassium humate and rice husk biochar on cherry tomatoes’ key soil chemical properties, yield and quality parameters. Methods: The experiment was conducted in the Can Tho University Department of Soil Science’s greenhouse. Experimental soil is alluvial soil collected in Tra On, Vinh Long. Two seasons (Summer-Autumn 2020 and Autumn-Winter 2020) were used for the experiment. The experiment design was completely randomized (CRD), with two factors: 9 treatments (corresponding to 9 fertilizer formulas), 4 replications and 4 plants each. Factor A (FA) is 3 levels of biochar rice husk application: 0 tons/ha (B0), 2.5 tons/ha (B1) and 5 tons/ha (B2). Factor B (FB) is 3 levels of potassium humate: 0 kg/ha (K0), 50 kg/ha (K1) and 100 kg/ha (K2). The experiment was conducted in a greenhouse at the Department of Soil Science, Can Tho University, using alluvial soil collected from Tra On, Vinh Long. The study spanned two growing seasons (Summer-Autumn 2020 and Autumn-Winter 2020). A completely randomized design (CRD) was employed with two factors and four replications. Factor A comprised three levels of rice husk biochar application: 0 tons/ha (B0), 2.5 tons/ha (B1) and 5 tons/ha (B2). Factor B consisted of three levels of potassium humate: 0 kg/ha (K0), 50 kg/ha (K1) and 100 kg/ha (K2), resulting in nine treatment combinations. Each replication contained four plants. Result: The experimental results showed that adding rice husk biochar and potassium humate improved soil P. Compared to the control (no biochar, no potassium humate), they significantly and statistically enhanced the amount of accessible nutrients (N, P and K) in the soil. The number of fruits/plants, fruit diameter, fruit yield, and percentage of Brix all significantly increased when cherry tomatoes were continuously monitored for growth, yield, and quality during both growing seasons while being treated with biochar husk and potassium humate. These results were statistically different from those of the control. The analysis of nitrate in tomato fruit showed that the nitrate of fruit was 23.45-24.94 (mg NO3-/kg fresh fruit), not exceeding the allowable threshold of 150 (mg NO3-/kg fresh fruit), and applying rice husk biochar and potassium humate significantly improved soil chemical properties compared to the control treatment. Notably, the soil’s availability of essential nutrients (N, P and K) was enhanced. Treatments with biochar and potassium humate throughout both growing seasons resulted in statistically significant improvements in various plant parameters, including fruit number per plant, diameter, total yield, and Brix content compared to the control. Fruit nitrate content ranged from 23.45 to 24.94 mg NO3-/kg fresh weight, remaining well below the regulatory threshold of 150 mg NO3-/kg fresh weight.