Abstract: Considering the problem of single design variable in traditional topology optimization methods for acoustic structure design, this paper proposes a design method for acoustic covering layer based on topology-parameter collaborative optimization. By using the genetic algorithm with elite retention strategy, a topology-parameter collaborative optimization model for acoustic covering layer is constructed, and both material distribution and matrix material parameters are taken as design variables. The optimized acoustic covering layer structure and material configuration are obtained. The design results show that in the full frequency band of 10 kHz, the average sound absorption coefficient of the topology-parameter collaborative optimization result reaches 0.862, which is 24.39% higher than that of the single topology optimization result, and the improvement effect of sound absorption performance is significant. However, in the low-frequency band, the sound absorption effect of the single topology optimization result is better. In addition, this paper explores the influence of material parameters such as Young's modulus on the sound absorption coefficient of the acoustic covering layer. This study provides a new method for finding underwater acoustic covering layer structures with broadband high sound absorption performance and suitable matrix materials.