In order to analyze the law of ground pressure appearing in the working face under the old goaf, the roof state of the working face was divided firstly, and the distribution of support pressure and the law of ground pressure appearing in the working face were analyzed by field measurement. The roof of Hufeng coal mining face can be divided into top coal + goaf and top coal + residual coal pillar of old kiln. The working resistance of hydraulic support increased sharply, generally higher than when it passed through the goaf. The cycle pressure time and step distance of the upper, middle and lower sections of the working face were inconsistent, and the step distance was 15~25 m.