As the core member in a software development team, the project manager's leadership level influences the development process in a great part. The existing literatures have shown the importance of individual's personality to his or her behaviors, which include the leadership behaviors. Exploring how the project managers' personality influences the success of the software development projects has significant potential utility. In this paper, we present a research integrating the Five Factor Model (FFM) for the personality with the existing work on the leaderships with the project success. Through the empirical study based on data from 116 software projects in real environment, we found general support for our hypothesized research model. The results not only reveal that the five big personality factors can be treated as indicators for the success of the software development projects, but also provide the evidence on how the project managers' personality influences the success of the software development projects through medium of the leadership constructs. The support for the relationship between leadership and the success of software development projects is also found.