This study aimed at investigating the role and impact of knowledge management on the job performance through HR at the Governor's Office, as well as unveiling direct and indirect relationship and roles between knowledge management as an independent variable and the job performance as a subordinate variable considering HR as a medium variable. This study has adopted the descriptive and analytical approach. The number of this study's community numbered to (2100) of the employees at the Governor's Office. The study's sample amounted to (325) employees who were selected by a simple random manner. The study depended on the questionnaire as a means of collecting data. It has used a number of advanced statistical approached in analyzing the study's measurement such as, Exploratory Factor Analysis (EFA), confirmatory factor analysis (CFA) for ensuring the structural credibility evidence for the study's managements. The programs of (SPSS) and (AMOS) have been used in this study to test statistical hypotheses for modeling the structural equation. The study's findings have shown in terms of structural modeling that the knowledge management has a positive effect on the job performance for employees at the Governor's Office as the impact volume amounted to (0.163) and this will contribute to a percentage of (16.3%) in enhancing the job performance of employees. These findings have also shown that the knowledge management have a positive impact on human resources, as well as due concern and attention paid by the Dhofar Governor's Office in managing knowledge through (Technological dimension, social dimension, organizational dimension and human dimension) and this will also contribute to a percentage of (13.2%) in enhancing human resources at the Establishment in question. The due concern and attention paid by Dhofar Governor's Office to HR through (HR planning, training and development, incentives, and bonuses) will definitely contribute to a percentage of ( 59%) in enhancing employees' job performance at the Establishment in question. The study's findings has shown rejection of the hypothesis which states that knowledge management has a positive impact on employees' job performance through the direct effect on HR at the Dhofar Governor's Office. Sobil's test findings for studying the in-between relationship has stated that there is no indirect impact of knowledge management on the job performance through HR as a medium variable as Sobel's test value amounted to (1.953) which is smaller than the specified standard (1.964). Therefore, the HR plays the partial mediator's role between both knowledge management and job performance. This study has recommended for concern and attention to be paid to intellectual environment that allows cognition and how to develop it and to be in harmony with working environment at the Office. The study has also proposed the establishment of a competent management to be concerned with knowledge to provide employees with modern and innovative contributions in relation to their specializations areas, as well as new changes relating to knowledge