This study has been in the field of Knowledge Management Processes and concepts of Knowledge Management System. The main purpose of present research was to examine the relationship between knowledge management with the improving professional activities in Customs office.. To this end, all experts’ employees of Customs Centers of the Iran have been evaluated. Method of this Research is Descriptive, in kinds of the Correlation, from the Applied Research. For Data collection, survey method is used and research sample consisted of all Customs experts employed in Kurdistan, Tehran and the headquarters office. The statistical methods applied in this study included descriptive statistics and inferential statistics. To examine the hypothesis the Pearson correlation coefficient was conducted, and also to analyze the research the confirmatory Path Analysis based on Structural Equation Modeling was used. Cronbach alpha reliability of the questionnaire method for two variables, respectively referenced 0.89 & 0.93 were calculated and verified. Final results of empirical study showed that all hypotheses have been confirmed and there are significant correlation between implementing KM and improving professional activities in Customs offices. The findings reflect the fact that individuals within Customs centers & similar organizations should use the KM processes of appropriate levels to generate new knowledge to accomplish their tasks.