The goal of the study was to assess the effect of capacity building on employee performance considering the mediating role of employee coaching and moderating role of managerial support. The study was based on quantitative, descriptive and correlational approach and designs. Convenience sampling technique was used in sampling 200 employees of GES in the East Gonja Municipality. SPSS was used for the descriptive and Cronbach Alpha analyses. Pearson Money Correlation analysis which was used to test the mediation and moderation effects were also performed through SPSS. The study revealed that capacity building has positive influence on employee job performance. Again, employee coaching showed statistically significance influence on employee job performance. Moreover, managerial support also showed positive effect on employee job performance. The study revealed that, employee coaching mediated the association between capacity building and employee job performance. Again, managerial support showed significant moderation effect on the association between capacity building and employee job performance.  It was recommended that capacity building, employee coaching and managerial support must become part of the human resource strategy of GES. This is because, capacity and receiving managerial support can aid in accelerating the competences, abilities, skills, commitment, loyalty and motivation of staff to deliver superior performance.