In order to strengthen the desorption performance of basic aluminum sulfate desulfurization rich solution, a negative pressure desorption experimental system was first built, and then the desorption kinetic equation of negative pressure 60 kPa was established by means of kinetic tools, the micro-mechanism and macro-performance of negative pressure enhanced desorption were further studied by comparing with normal pressure desorption. The results show that the maximum instantaneous desorption rate appears at the initial time of desorption reaction. The desorption reaction rate r is proportional to and [H ⁺]^{0. 61± 0.02}, the activation energy E_a is (22.78 ± 0.12) kJ/mol, and the pre-exponential factor A is (12 332.58 ± 0.36) L^{0. 97}/(mol^{0. 97}·min) . The reaction rate constant k is the main factor affecting the desorption reaction rate. The E_a and A of negative pressure desorption at 60 kPa are 0.55 times and 0. 01 times that of normal pressure desorption, respectively. The negative pressure effectively enhanced the macroscopic desorption performance of atmospheric desorption at the same temperature. The increase degree of desorption rate of negative pressure relative to atmospheric pressure at different temperatures reaches the maximum value of 25.06%、28.44% and 21.78% respectively at 50 min. The increase of desorption rate at the end of desorption is maintained at (3.36 ± 0.18) × 10 ^-4 mol/(L·min) . The research results provide reliable theoretical support for the application of basic aluminum desorption desulfurization.