The invention discloses an adaptive car body height adjusting method based on multi-source information fusion. The car body height adjusting function of an electronic-controlled air suspension (ECAS)system is mainly utilized to achieve the purpose of lowering oil consumption. The adaptive car body height adjusting method comprises the implementing steps that route pre-judging information, currentroad condition information, weather state indicators and the car speed are obtained based on a multi-source sensor; the information is used for establishing a decision tree model, specifically, the three links of selecting and processing of sample data, splitting of a tree and establishing of the decision tree model are included; during real-time traveling, the information obtained by the sensoris input into the decision tree model, the target height of a car body is output, and car height adjusting strategies are combined to output a control signal meeting the demands; and finally, the adaptive car body height adjusting function is realized, and the purpose of lowering oil consumption is further realized. According to the adaptive car body height adjusting method, a variety of information is fused, the information amount of decisions is enriched, the accuracy of decision judgment is improved, meanwhile, the car safety property is considered when the model is established, and the safety guarantee is provided for adjusting the car height.