Because the microperforated panel structure cannot achieve high-bandwidth absorption under low-frequency noise， it is necessary to optimize the structural parameters of the sound absorber to achieve the required absorption level in order to improve the low-frequency sound absorption performance. In this research， the single-layer microperforated panel structure with the variable parameters and separated cavities is optimized and tested. This structure has a high sound absorption coefficient at low frequencies and a sound absorption bandwidth. Theoretical model of the single-layer microperforated panel structure with variable parameters and separated cavities is established by the acoustoelectric analogy method， and the relationship between the sound absorption coefficient and the structural parameters is analyzed. Through determining the optimization variables and constraints and using the cuckoo search algorithm to optimize the theoretical model， the optimal structural parameters are obtained to achieve the best sound absorption performance. The sound absorption coefficients of the microperforated panel structure are subjected to finite element simulation， and samples of the microperforated panel structures are processed and tested in a standing wave tube measurement. The results show that the single-layer microperforated panel structure with three or four sets of structural parameters and separated cavities can ensure high sound absorption （constantly more than 80%） in the frequency range of 400~2 000 Hz.