Managing diabetes requires continuous glucose monitoring (CGM) to maintain homeostasis. To overcome the limitations of invasive blood sampling and unstable sweat collection in wearable sensors, we introduce a photonic sweat glucose sensor integrated with a Tesla valve-based microfluidic system. This geometry ensures continuous, evaporation-free, and unidirectional sweat flow with minimal backflow, facilitating stable acquisition. The sensing mechanism employs a glucose-responsive hydrogel matrix embedding glucose oxidase and an oxygen-sensitive phosphorescent dye. Using a smartwatch’s green LED for excitation, glucose levels are determined by analyzing fluorescence intensity changes. In vitro experiments validated a detection range of 0.01 mM to 1 mM. Furthermore, human trials demonstrated a strong correlation between sweat and blood glucose levels. This study shows the feasibility of integrating functional hydrogels with microfluidics for non-invasive wearable CGM.