Curcuma longa L. (CL) is a well known traditional medicinal plant that is also used in curries and mustards as a coloring and flavoring agent. However, CL is not usually used as a food source due to its bitter taste. We investigated the immunomodulatory effect of CL fermented by Aspergillus oryzae (FCL) on RAW 264.7 cells. FCL was extracted with cold water (CW), hot water (HW), 20% ethanol (20% EtOH) and 80% ethanol (80% EtOH), after which its effects on phagocytic activity, tumor necrosis factor-alpha (TNF-α), nitric oxide (NO) production, natural killer (NK) cell activity and mRNA expression of LP-BM5 eco were investigated. Phagocytic activity was increased in HW and 20% EtOH when compared to the control. The secretion of nitric oxide (NO) from RAW 264.7 cells did not change significantly relative to the control. However, TNF-α was significantly increased by the addition of FCL extracts. Moreover, FCL 20% ethanol extract showed a four fold increase in NK cell cytotoxity relative to the control group. Finally, we observed suppressed mRNA expression of LP-BM5 eco in FCL extracts, especially in the 20% ethanol extracts group. These results indicate that the FCL extracts can be used as a functional material due to their effective immunomodulating activities.