Risk of the IT Project's Time is one of the most important risks in IT projects. Most of the existing IT engineering time risk metrics is directly based on Experts Grading Method metric results, so the accuracy of the results is not enough to bring the practical application of the inconveniencing. In order to solve this problem, two different analytical paths are proposed in this paper. The first risk measurement method is to measure the risk in the specific distribution assumptions on IT Project's time; the second one is using the Monte Carlo simulation to measure IT project time risk. And finally, the risk of a simple small-scale IT projects Time is measured using the two methods. The result shows that the measure IT project time risk method using Monte Carlo simulation can meet the precision, and it is applicable to a wider area.