Background: This study evaluated the effect of the Benson relaxation method on the quality of sleep and working life of surgical technologists. Methods: This randomized controlled trial was done on 180 surgical technologists who worked in 9 hospitals in Shiraz. Before the beginning of the intervention, participants were randomly assigned to either experimental or control conditions (simple randomization). The experimental group listened to an audiotape of the Benson relaxation technique twenty minutes periods, two times a day for four weeks, while the control group did not receive any intervention at all. The Pittsburgh sleep quality index and Walton quality of working life (QWL) questionnaires were used to measure the sleep quality and working life of surgical technologists, respectively. Results: Independent t-tests indicated that after the intervention, there were significant improvements regarding the total mean scores of quality of sleep (Mean (SD) Intervention = 2.88 (1.36), Mean (SD) Control = 15.1 (3.41), P < 0.001), and working life (Mean (SD) Intervention = 133.78 (9.22), Mean (SD) Control = 62.18 (19.68, P < 0.001) and their domains in the intervention group compared to the control group. Conclusions: Our findings are an important contribution to the previous research regarding the Benson relaxation technique as a non-drug, economical method. The current results can help health professionals for determine which psychological techniques are needed to be emphasized for promoting sleep quality and quality of working life in surgical technologists.