Abstract: It has been found that opportunity evaluation is a key factor in entrepreneurial cognitive theory.71 small business entrepreneurs and 82 corporate managers are investigated in terms of their evaluation to entrepreneurial opportunities.It is found that entrepreneurs' cognitive mechanism could be considered as a process.In the process,either entrepreneurs' cognitive biases directly or through their risk perception indirectly affected their opportunity evaluation.It is also found that entrepreneurs take more cognitive biases than corporate managers.

Key words: entrepreneurship, opportunity evaluation, entrepreneur, manager