Identifying risk factors in software risk management is imperative for project managers. The purpose of this paper is to provide software project risk factors validated by statistical analysis, and thus to help project managers alleviating the possibility of software project failure. Factor analysis with data collected from 264 Korean project managers and consultants identified 12 categories and 46 risk factors. T-test results showed that project managers and participants had statistically different perception on 3 risk factors among those 46 risk factors. We concluded by discussing implications of our findings and future research directions.