Abstract: Micro-perforated panel sound absorber (MPA) as an efficient sound absorption structure has great potential for the application in the field of noise control. However, the conventional single-layer micro-perforated panel (MPP) is difficult to respond to the variable noise environment due to its narrow sound absorption band. Therefore, a single-layer inhomogeneous micro-perforated panel sound absorber with built-in perforated partition was proposed in this work. Firstly, the equivalent circuit model of the proposed acoustic structure was established and analyzed theoretically. And then the parametric simulation study of the structure was conducted with COMSOL Multiphysics finite element software, followed by the experimental analysis. The analysis results show that the partition perforation can adjust the acoustic impedance of the absorber effectively, therefore broadening the absorption bandwidth of the absorber structure. This work provides new ideas for the popularization and application of micro-perforated panel absorbers.