The paper tried to quantify the risks that the high-tech firms faced in terms of the circumstances variance, took the long-term debt rate as the proxy of the capital structure in high-tech firms. Then, combined with the examination on the growth of high-tech firms, the paper conducted an empirical research on the relationship between environment risk, capital structure, growth and firm performance in high-tech firms. The result of the research showed that there exists a significant correlation between environment risk, growth and high-tech firms' performance.