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Ecological restoration may be used to mitigate the adverse effects on biodiversity caused by the degradation or loss of pristine rainforests. However, long-term studies on biodiversity recovery in such restorations are lacking, especially concerning animals. Intending to evaluate the utility of restoration for biodiversity conservation, this study investigated how trees and sound-producing vertebrate animals recover across a large-scale restoration in Sabah, Malaysia. The tree community was investigated through a field inventory, and forest characteristics relating to tree diversity, tree species composition and forest structure were investigated. The fauna was inventoried using audio loggers and pattern-matching analysis. Forest characteristics and animal richness of restored forests were contrasted against degraded and pristine forests to investigate recovery. Additionally, relationships between the forest’s state and animal richness were explored. After 25 years, tree diversity showed some evidence of recovery. Forest composition had fully (e.g., the proportion of dipterocarps) or partially (e.g., tree composition) recovered following restoration. Forest structure showed few signs of recovery, with similar tree coverage across all forest types and no signs of recovery in tree size variability. Total animal richness was high across forest types and was related to forest composition. Red-listed animal richness had recovered in restored forests and was related to the forest's composition and structure. The recovery of the tree community and red-listed animals exemplifies the utility of rainforest restoration for ecological conservation. However, considerations of forest structure may improve future restorations. Finally, the similar total animal richness across forest types indicates some conservational values of degraded forests.