Measurement of the performance of a company is very important to evaluate andplan the future. Employee performance assessment absolutely must be done to determine theaccomplishments to be achieved every employee. For that every company has a different wayof assessing employee performance. In practice, the assessment of the achievements ofemployees should be done with a good method and precise, so there is no error in judgement.The results of the assessment should ensure fair treatment and satisfactory to the employeesassessed, so that in turn foster loyalty and morale. There are several tools that are commonlyused to assess employee performance. Decision support system is a tool that can be used toassess employee performance by improving methods of assessment of the performanceappraisal. Fuzzy Simple Additive weighting method chosen for assessing and ranking theemployees' performance. From the test results can be concluded that this application can beimplemented for the performance appraisal in Klinik Pengobatan Keluarga Kita. To the authorstried to propose a study that the authors give the title: “application methods of Fuzzy SimpleAdditive Weighting (FSAW) On Employee Performance Appraisal in Klinik PengobatanKeluarga Kita Jakarta” Keywords: FSAW, Assessment of Employee Performance, Support System Decision, Loyalty,Performance.