Abstract: Engineering risks are of objective reality and subjective construction. Different engineering subjects may have varied risk perceptions of the same engineering risk. Furthermore， their risk perceptions are susceptible to change due to such objective factors as risk nature， risk familiarity and disaster degree， risk unpredictability and uncontrollability， and such subjective factors as engineering subjects risk knowledge， attitudes and cognitive strategies. Therefore， in order to eliminate or reduce risk perception differences， such perspectives should be taken as engineers subject responsibility ethics， risk communication ethics among different engineering subjects and decision-making ethics of social stability assessment so as to evaluate risks reasonably and avoid or control risks effectively.

Key words: engineering risk, risk perception, social stability assessment, risk communication