An optical blood glucose detecting apparatus and an operating method thereof are disclosed. The optical blood glucose detecting apparatus includes a detecting module, an assisting and strengthening module, and a data processing module. The detecting module provides an incident optical signal passing through a detected portion of skin surface into a skin interstitial fluid, captures a blood glucose optical reflection message of the skin interstitial fluid, and it interferes the blood glucose optical reflection message and the incident optical signal to generate a detected data. The assisting and strengthening module provides a physical or chemical effect on a tissue region under the detected portion to strengthen the blood glucose optical reflection message. The data processing module processes the detected data to determine a blood glucose concentration.