In this study, we propose a novel method to determine the vitamin C content in fruits and vegetables. The proposed method exploits the image and data processing abilities of computers by coupling a digital camera and a color reaction. An image acquisition device was developed to collect the image information of the solution to be measured after the color reaction. The corresponding RGB and Lab color components were obtained by an image analysis software. Further, the standard curves of the vitamin C concentration and color component were established by nonlinear, linear, and multivariate data fitting. The detection range was 0.81-20.00 µg mL-1 (R2 = 0.9994), LOD was 0.24 µg mL-1, LOQ was 0.81 µg mL-1, accuracy was 98.95%, and precision was determined with an RSD of 0.73%. A comparison of the results confirmed that the proposed method’s accuracy was higher than that of the spectrophotometric method. The proposed method has a simple design and facilitates easy operation, and the cost of the equipment is only US$ 31.43. Therefore, it can replace the traditional spectrophotometric method for the determination of vitamin C content in fruits and vegetables and is highly applicable in the food, chemical, and medical fields.