Abstract: The three-D heat-force coupling analysis of the rotary rolling process of the round bloom in the piercing preparation zone during rotary piercing operation was carried out with MARC/Autoforge Software,identifying characteristics of distribution of stress/strain field and temperature field which conform to the result of the physical simulation conducted.This research conclusion suppots the theory of “Composite Stress” involving formation of central cavity of the solid bloom during rotary rolling.Moreover, some new characteristics of stress distribution have been identified.