Introduction: Cancer is the second leading disease responsible for causing death worldwide. Under normal circumstances, cells of living creatures undergo division. However, excessive cell division is one of hallmarks of cancer. Efforts are used to treat cancer with low side effects by using herbs which are potential to act as anti-mitotic substances, such as pigeon pea (Cajanus cajan) which contains flavonoids, tannins, alkaloids, saponins, cyanogenic glycosides, glycosides, and anthocyanins which have the anti-inflammatory, anti-cancer, immunomodulatory, and also antioxidants properties. The study aims to determine the anti-mitotic activity of the pigeon pea (Cajanus cajan) filtrates to sea urchin (Diadema antillarum) embryonic cells. Methods: This study was experimental research in laboratory. This study used 5 replications for each dose of filtrates (5%, 10%, 15%, 20% and 25% ) and cell division processes was observed at following specific time: every 15 minutes until the first division stage (to produce 2 cells), every 1 hour for the second division stage (to produce 4, 8, 16, and 32 cells) and every 24 hours to microscopically observe the blastula, gastrula and plateus. The results were observed in 10 high-power fields. Data were then analyzed with an ANOVA test using IBM SPSS 25. Results: The result shows that on every treatment groups there was a decrease in the percentage of sea urchin embryonic cells which underwent division at each stage of cell division and was significantly different (P<0.05). Conclusion: Pigeon pea filtrates showed an antimitotic activity to sea urchin embryonic cells (P<0.05).