Abstract: In view of problems of low automation degree and recognition reliability of digital display instrument in coal mine substation, a kind of character recognition algorithm based on improved genetic algorithm and support vector machine algorithm was proposed. The algorithm adopts Harr-Like features as character recognition features, improved genetic algorithm was chosen to search the optimal parameters of the support vector machine classifier, and uses principal component analysis method to conduct the dimension reducing process, then applies support vector machine to identify character of the digital display instrument. The effectiveness and feasibility of the algorithm was validated by experiments.