Abstract: Based on the “support-unloading” combined technology for gob-side entry retaining, establishment mechanics model for buried height working face of SanJiang coal mine. Pressure relief height and roadside support strength obtained by theoretical calculation method, and used in industry application. The results showed, end support resistance decreased by 12% after hydraulic fracturing, the maximum load of pillar reached 27.9MPa without damage, which proved that 1m concrete pillar support strength fitted shallow buried height working face with 92m depth and 5.24m height mining. The moving quantity of roof and floor was 83mm, the maximum roof abscission layer was 23mm during gob-side entry retaining period. It can provide technical reference for mining without pillars under similar conditions.