One of the most important issues faced in organizations is the objective performance measure of employees who have a crucial role in the success of the production/service processes. Performance appraisal is vital since it helps to clarify whether the company is going in line with the predetermined objectives. Performance appraisal is the evaluation of the general performance level of personnel according to the previously determined targets and/or performance factors. The main purpose of performance appraisal is not only to increase the performance of employees, but also to unite the individual targets with the company's targets. Performance appraisal requires evaluation and decision making in uncertain environments involving multiple factors. In this paper, a performance appraisal model is constructed to deal with the uncertainty and also to objectively measure the employees' performances. The criteria used in the model are defined in terms of the fuzzy numbers and linguistic variables. The three main criteria of the performance appraisal model are decision making and leadership, communication and relations, and technical skills. The model is applied in the purchasing department of a company operating in the automotive industry. The developed model has the flexibility to be applied in different departments with a modification in the criteria under the title of "Technical skills".