Soil macrofauna are essential indicators of ecosystem health and sustainability in agricultural systems. This study compared soil macrofaunal communities in oil palm–banana intercropping systems (ICS) and monocropping systems (MCS) within replanting areas of Bengkulu, Indonesia. ICS produced higher biomass and litterfall than MCS, contributing to greater soil organic matter. Species richness was similar between systems, but ICS showed higher Shannon-Wiener diversity (H′) and evenness (J′) indices. Diverse taxonomic groups, including earthworms, beetles, centipedes, and millipedes, were more abundant in ICS, while MCS was dominated by ants and exhibited lower diversity and evenness. Significant positive correlations were observed between litterfall, biomass, and biodiversity indices, indicating the role of organic inputs in supporting soil macrofaunal populations. These results demonstrate that intercropping creates more heterogeneous habitats and supports more balanced ecological communities than monocropping. The study provides baseline information on soil biodiversity in oil palm replanting systems and underscores the potential of intercropping practices to enhance soil health and support sustainable land management.