Diabetes is increasingly threatening human health. However, noninvasive blood glucose detection methods for clinical use have not yet been developed. To solve this crucial problem, we study the spectral characteristics of light source through different mass concentrations of glucose in a solution. The wavelength range is 600-1300 nm, and the absorption spectral characteristics of glucose solutions with different mass concentrations and the reflection spectral characteristics of 2% Intralipid tissue phantoms with different glucose mass concentrations are studied. The spectral characteristics are evaluated based on their monotonicity, linearity and sensitivity. Experimental results show that light waves are absorbed in the range of 1140-1210 and 1130-1200 nm and those reflected in the range of 1010-1130 and 1150-1300 nm exhibited monotonicity, excellent linearity, and high sensitivity. Thus, light waves with these characteristics are expected to realize noninvasive blood glucose detection and also to improve accuracy and sensitivity, thereby promoting the application of optical noninvasive methods in clinical blood glucose detection.