A multi-sensor non-invasive blood glucose monitoring instrument based on impedance spectroscopy-optical method, which belongs to a blood glucose measuring instrument for human body. The blood glucose monitoring instrument comprises a detection probe, a microprocessor, a display unit and a storage unit. The detection probe comprises a temperature and humidity sensor, an LED array, a photoelectric sensor, a pair of low-frequency electrodes, and a pair of high-frequency electrodes. The high-frequency electrode employs parallel electrodes, a matching inductor is directly soldered to the positive electrode or negative electrode of the electrode, and a shielding electrode is provided around the high-frequency electrode. The distance between the two low-frequency electrodes is 1 cm-2m, and the low-frequency electrodes can test the low-frequency impedance of the tissue stably. The temperature and humidity sensor and the tested part of human body form an enclosed space, and slits or pores are arranged in the wall of the enclosed space to form a balanced heat and moisture storage structure. The non-invasive blood glucose monitoring instrument incorporates the impedance spectroscopy method and the optical method, and can obtain more accurate blood glucose levels with improved sensor design.