The species composition of bee and non-bee Hymenoptera in the Tengku Hassanal Wildlife Reserve (THWR) Forest, Pahang, Malaysia, was studied to document their diversity and to explore their relatedness using DNA barcoding of the cytochrome c oxidase subunit I (COI) region inferred by Neighbour-Joining tree. DNA of 56 specimens were successfully extracted from the trapping between February 2023 and January 2024 by using 12 malaise traps. The collection represents 34 species from 33 genera across 11 families; eight families identified as an effective pollinators (Apidae, Halictidae, Liopteridae, Tenthredinidae, Crabronidae, Pompilidae, Tiphiidae and Vespidae), while three families were classified as less effective pollinators (Braconidae, Evaniidae, and Ichneumonidae). Unique DNA sequences revealed limited or no matches in global databases, highlighting Malaysia’s underexplored hymenopteran diversity. This study provides essential baseline data on pollinator diversity, emphasizing the roles of effective pollinators (Apis cerana, Tetrigona apicalis) and less effective pollinators (e.g., parasitoid wasps) through flower visitation in sustaining ecosystem stability. The inclusion of genetic tools alongside morphological approaches offers valuable insights for biodiversity conservation and highlights the global importance of preserving tropical ecosystems.