Aging is a process that begins at birth and ends with death. This process is accompanied by environmental effects, which cause structural and functional changes in cells and tissues. With regards to healthy aging, melatonin significantly extends lifespan. This study aims to show the anti-aging effects of melatonin on lifespan by a model organism called Caenorhabditis elegans. The nematode strain N2 (wild-type) was acquired, and E. coli OP50 was used in the study, Worms were grouped into a control group (n=100), and six experimental groups (group 1, 2, 3, 4, 5 and group 6) (n=100 in each of them). Interventions were made by exposing Caenorhabditis elegans to various dosages of melatonin and follow up was made for 21 days. The survey of Caenorhabditis elegans, which depends on time and dosage as the main outcome measures, was examined microscopically. Different dosages of melatonin affected the lifespan and morphology of Caenorhabditis elegans. Melatonin might be used in the prevention of aging.