Curcumin is an active ingredient in Curcuma longa.It contains essential antioxidant, anti-inflammatory, antiviral and antifungal actions.Formaldehyde is a clear, colorless, volatile liquid which has a pungent odor and slightly irritating taste.Formaldehyde is one of the chemical substances which activate breast cancer cell progression.This study investigated the effect of curcumin induces apoptosis in breast cancer cell (MCF-7) treated with formaldehyde.MCFo 7 cells were treated with 100 nM formaldehyde for 24 hours.Formaldehyde treated MCF-7 cells were cultured with 10, 50 and 100 μM curcumin for 24 and 48 hours respectively.Cell count and MTT assay were done for detect the formaldehyde treated MCF-7 cell apoptosis by curcumin.The results showed that the mortality rates of formaldehyde treated MCF-7 cell with 10, 50 and 100 μM curcumin for 24 and 48 hours were increased depending on the curcumin dosage and the curcumin treated time.The treated time was more effective for apoptosis than the dosage.Curcumin induces apoptosis in formaldehyde treated MCF-7 cell.Curcumin may be useful for breast cancer treatment.