Objectives: We applied surgical techniques acquired during use of the endoscopic combined transseptal/transnasal approach to reduce approach-related morbidity and improve sinonasal outcomes. Study Design: Retrospective cohort study of a prospectively collected database. Setting: A tertiary referral center. Participants: A total of 86 patients who underwent endoscopic endonasal transsphenoidal surgery for newly diagnosed pituitary adenomas from April 2018 to March 2021 were included. Patients treated via the combined transseptal/transnasal approach served as the study group(n=18); those treated via the bilateral transnasal approach comprised the control group(n=68). From the control group, propensity score matching(PSM) analysis was further performed to account for potential confounders and selection bias. Main Outcome Measures: Paired analysis was performed for pre-and 6-month-postoperative time points in study group, control group, and PSM control group. Olfactory function was evaluated by Connecticut Chemosensory Clinical Research Center (CCCRC) test, Cross-Cultural Smell Identification Test (CCSIT), and sinonasal outcomes were assessed by Sino-Nasal Outcome . Results: In the study group, CCCRC (p=0.517) and CCSIT (p=0.497) did not show any significant difference before and after surgery. There was some improvement in the symptom score of SNOT-22, but it was not statistically significant (p=0.115). In the control group adjusted with PSM, a significant decrease in olfaction (p=0.047) was observed using CCCRC. The CCSIT score was also decreased but not significant (p=0.163). Also, there was no difference in the improvement of . Conclusions: Our new surgical method preserves olfactory function without compromising surgical outcomes.