Regional overheating dead pixels problems of InSb infrared focal plane detectors was studied. Through fault analysis and targeted investigation and comparison tests, factors such as packaging, glue filling and dicing are eliminated, and the fault is located before the passivation process. Through the X-ray photoelectron spectroscopy test on the surface of InSb materials before passivation, it is found that it contains impurity elements such as Al and As, and the surface of the material contains more impurities before passivation. Impurity elements form impurity levels in the depletion region of the PN junction. Impurity elements form impurity levels in the depletion region of the PN junction. After voltage is applied, it is easy to cause high leakage current of the PN junction, degrade the I-V characteristics, and form overheating dead pixels. By reducing the washing liquid replacement period of the cleaning appliance and separating the appliances of multiple production lines, the content of impurities on the surface of the material is reduced, and the problem of regional overheating dead pixels is effectively solved.