In contrast with contingency theories in strategic human resource management that emphasize on the best fit between business strategies and HRM strategies for achieving higher performance, universalistic approaches emphasize that there are some best human resource management practices and strategies that always leading to higher performance. This research aimed at empirical test of universalistic theory and identify the best HR practices in 100 high performance firms in Tehran Stock Exchange. The results, based on analysis of questionnaires completed by 43 firms show that there is one best strategy (facilitation strategy) and some best HR practices in human resource management that can lead Iranian firms to higher performance.