Provided is an infrared / laser radar data fusion target tracking method based on a multi-scale model. The method comprises the steps that the multi-scale model is built; data collection is carried out on a target, and the distance measurement value, the azimuth angle measurement value and the pitch angle measurement value of the target are obtained; estimation is carried out on angle information obtained by an infrared detection system on a scale 1 through the unscented Kalman filter method; the angle estimation information and the distance information are fused on a scale 2; the target state is estimated through the Kalman filter method on the scale 2; the fused and estimated information is converted on the scale 1, filtering estimation is carried out on the scale 1 through the Kalman filter method, and an accurate filtering estimated value is obtained; the above steps are repeated, and a target movement track is obtained. The multi-scale model is quoted into information fusion, the target movement state is described more comprehensively and accurately, estimation filtering is carried out on the target on different scales, the estimation precision of the target state is improved, and the target tracking precision is improved through information interaction between different scales.