The work aims to measure the solid-liquid height of blood card after filling and check whether bubbles exist in the liquid filled. Six independent micro pipes were obtained by rotation correction, initial cutting and positioning segmentation of blood card images captured by cameras. The horizontal edge position between solid-liquid mixed phase and liquid phase was extracted in the method of Sobel horizontal edge detection. Then, the corresponding height was calculated. Meanwhile, the way of detecting bubbles based on SVM was put forward. The HOG characteristics of the bubble were extracted, and the RBF kernel function was selected to train the detection model and establish the classification model. The best model parameters were obtained by the way of cross validation. Compared with manual measurement results, the error of solid-liquid mixed phase height was less than ±0.1 mm, the error of liquid phase height was less than ±0.2 mm, and the detection accuracy of bubbles was more than 97%. The need for real-time detection could be met in efficiency. The total time of height measurement and bubble detection was lower than 1.5 s, which met the real-time requirements. The detection system designed can solve online detection problems of blood card filling quality effectively.