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Based on the nearly 100 m² large section chamber for large mining height support reloading, with the site observation and numerical simulation method, surrounding rock deformation and failure mechanism was analyzed. With the increase of chamber section, the failure zone and the plastic zone increase, the plastic zone radius of super large section chamber is 2.2 times about normal section chamber. The high disturbed stress because of large section, the small thickness of anchorage body with bolt support, and the low initial support resistance resulted in serious deformation and failure of weak surrounding rock. According to the 0-2.5 m failure zone and the 2.5-8.0 m plastic zone of support reloading chamber, the stability principle of zonal control of coupling support for large cross section chamber was put forward. After chamber excavation, the failure zone, the plastic zone and the elastic zone were formed, the surrounding rock damage degree was gradually reduced from shallow to deep, and also the needed support strength to be stability decreased gradually, through the high strength and high pre-stress support with bolt, grouting cable and cable, three load bearing ring can be formed according to the failure zone, the plastic zone and the elastic zone, so that the three zones are connected organically, and the support strength for the three zones can be satisfied, and a common loading of supporting structure and surrounding rock can be ensure the stability of the surrounding rock. [ABSTRACT FROM AUTHOR]