This study explored the effect of music on improving biological parameters in preoperative patients. In this quasi experimental research design, 114 subjects receiving the patients for laminectomy were recruited from March 1, 2009 through August 30, 2009 at a Medical Center in Taichung City, Taiwan. Volunteers were assigned to either a study group (62 patients) or control group (52 patients). Baseline vital signs were obtained in waiting room before the study. Subjects in experimental group listened to the music through earphones in the waiting room. Subjects in the control group only received routine preoperative procedures. For both groups, vital signs were checked at 10 mins, 20 mins and 30 mins . The data were descriptively analyzed by ANCOVA, repeated measure ANOVA and LSD post hoc examination. No difference was found in systolic pressure. However improvements were found in diastolic pressure, heart and respiratory rate in those who listened to music. Post hoc examination of LSD indicated that all biologic factors except diastolic pressure decreased after 20 minutes of music intervention. With regard to diastolic pressure, there was an initial increase at 10 minutes which decreased in the subsequent tests. The results suggest music might be used to decrease anxiety in pre-operative patients.