For amphibians, there are about 4,960 individual or lot of specimens representing some 325 species, with type material for around 30 nominal species. For reptiles (orders Squamata, Testudines, Crocodylia), there are about 7,780 individual specimens representing around 607 species, with type material for some 75 nominal species. Most of the specimens are kept whole in liquid preservatives, while larger turtles are usually stuffed and dried.

A large part of the herpetological collection originated from the Malay Peninsula, including Singapore, with significant representation from Borneo, Sumatra, Java and Thailand. Recent specimens consist of locally sourced roadkills and other carcasses donated by the public and the Singapore National Parks Board.

A collection of sea-snakes (Aipysurus and Hydrophis spp.) with at least 18 species amassed in the 1980s from fishing ports in Singapore and Malaysia is noteworthy. A large leathery turtle (Dermochelys coriacea) found at Siglap in 188 is a unique historical record of this species in Singapore. Two blood pythons (Python brongersmai) collected in Singapore in 1901 and 1903 appear to be physical evidence that the species is likely to have become extinct in the country. The estuarine crocodile (Crocodylus porosus) is believed to be the largest extant species of reptile. There are two skulls of this species in the collection that are exceptionally massive and the whole crocodiles are estimated to have been at least 6 m in length.