A portable light source and power meter system has been designed based on a digital supermode distributed Bragg reflection (DS-DBR) laser and an InGaAs photodetector. The light source module of the system uses both the OPA569AIDWP chip and the ADN8834 chip as the controlling core, providing excellent control of the wavelength accuracy and power stability. The power meter module employs the multi-grade amplification range control and insulation denoising technologies along with the software algorithms, which significantly suppresses the system noise and improves the sensitivity and dynamic range of the power meter. The test results demonstrate that the light source module can effectively control the output light wavelength. Also, the side-mode suppression ratio of the output light is higher than 50 dB, and the linewidth is smaller than 1 MHz with satisfactory output quality. Furthermore, the dynamic range of the power meter module reaches 80 dB, and the linearity is increased to 0.08 dB. In addition, our system adopts an embedded control technology to allow human-computer interaction; thus, it can be applied to various settings such as laboratories and industries. Therefore, with such attractive and broad market prospects, the application range of our portable system is considerably broadened.