This study dealt with the ant species that were identified on albino rat (Rattus norvegicus Berkenhout, 1769) carcasses in two habitats ecologically differentiated in Riyadh. The study was conducted from 14 January to 23 February 2018, at Al-Dir'iya, Riyadh, Saudi Arabia. A total of 502 ants in three subfamilies and seven species were classified and recorded during the putrification process. From the carcasses placed in a botanical garden, Tapinoma magnum, Tetramorium sericeiventre, Tetramorium semilaeve, Monomorium sp., Paratrechina longicornis, Camponotus fellah and Cataglyphis albicans were recorded. But, from the carcasses kept on the building roof of the college a Tapinoma magnum and P. longicornis were only recorded. The carcasses at the botanical garden involved the maximum number of ants compared to the carcasses at the roof. The most-encountered species at both sites was T. magnum. This study showed that ant species could be present during the bloat, decay and dry stages of decomposition, demonstrating they were not an indicator of insect succession. This data suggest that specific ant species of the Formicidae family could play critical roles in forensic entomology and as biological tools in criminal investigations in Al-Dir'iya, Riyadh, Saudi Arabia.