The noninvasive blood sugar measurement device contains a device body, a sensor, a processing module, and an error reduction module. The sensor is configured on a side of the device body for detecting a glucose level in perspiration. The processing module and the error reduction module are configured inside the device body. The processing module is data-linked with the sensor for calculating and converting a measured glucose level into a corresponding blood sugar level. The error reduction module is data-linked with the processing module for reducing a progressive error accumulated by the sensor from repeated detection of perspiration glucose level. The present invention therefore completely avoids invasive means such drawing blood and puncturing skin.