This paper takes professional titles and posts as the independent variables and the competency of library managers as the dependent variable,trying to analyze the impact of professional titles and posts on competency.It finds out that library managers with different professional titles differ in executive and problem-solving abilities;managers in the posts of technology,novelty assessment and consultant are weak in the basic knowledge and skills and the traits that the jobs need;professional titles and posts have significant interaction on managers’ abilities for research and service consciousness.