The acid red soil is widespread in south China which characterized as low pH and water holding capacity. Biochar, a cheap and widely used carbon-rich material, has shown the potential to ameliorate the degraded soil, but its effects on the dry land acid red soil are still unclear. Hence, a pot experiment of aridity simulation was conducted with different application content of biochar (0, 1%, 2%, 3%, 4%) added in the acid red soil and watered with 1 L distilled water equally, then soil water content, pH, electric conductivity, NH₄⁺-N, NO₃^--N and available phosphorus were measured after one month of aridity simulation. Results showed that soil pH, electric conductivity and available phosphorus increased and NH₄⁺-N decreased significantly with the increase of biochar application, while NO₃^--N changed insignificantly. A quadratic relation was observed between soil water content and the content of biochar application, soil water content was decreased significantly under low application content (1%) but increase significantly under high content of application (4%). This study provides a basis for the biochar application in ameliorating the acid red soil in south China.