The situational   theory of problem solving，which is a New theory of public relations, was presented by Kim J.-N and Grunig, J. E. The theory introduces problem recognition, constraint recognition, involvement recognition, and referent criterion as independent variables, situational motivation as moderator variable，information seeking, information attending, information forefending,  information permitting, information forwarding, information  sharing as dependent variables, to explain people how and why communicate in the situation of problem solving. the theory is an extended and generalized version of the situational theory of publics, which was challenged in the past ten years. It is necessary to explore its theory meaning and practical value.