As an important part of capital theory, psychological capital plays an important role in the researches of human behavior. This paper focuses on “the relationship between psychological capital and performance of knowledge worker”, takes knowledge workers of high-tech enterprise in Zhejiang Province as research object, establishes structural equation model to empirical research, then uses AMOS software to analyze the model and data, and explores the role and size of relationship between the variables. The results showed that psychological capital is stably positively related to the performance of knowledge worker. Among them, confidence and resilience is obviously positive correlation with each dimension of performance, while there is no-relevant between hope and task performance, and the same as optimism and job devotion.