Objective: To determine the anti-breast cancer activities and the safety oral consumption of Dillenia suffruticosa root aqueous extract (DRAE) in BALB/c mice. Methods: In the anti-breast cancer study, female BALB/c mice were divided into five groups (n = 12), which were (1) positive control (with breast cancer, untreated), (2) negative control (without breast cancer, untreated) and other three groups of mice with breast cancer treated with 1000, 500 and 250 mg/kg of DRAE, respectively, by oral gavage for 28 days. All mice except from the negative control group were injected into the mammary fat pad with 4T1 cells (1 × 10