Due to the characteristics of large span, complex structure, and liability to the disturbance of operation, cross sections of deep engineering are somewhat difficuh to support. Through the field investigation in geological condition, a difficulty coefficient and the eorresponding supporting types and parameters were determined. Four primary deformation mechanics, i.c. mechanics of tectonic stress interaction, mechanics of self-welght stress interaction, mechanics of structure deformation, as well as deformation related to operational sequence were summarized out. Based on the analysis of these deformation mechanics, the cable and bolt supporting parameters and operation sequences were optimized. The supporting plan was put into operation and a sound effect has been achieved.