Chronic rhinosinusitis may cause olfactory dysfunction and affects quality of life in patients. In a prospective study we investigated the effect of topical application of corticosteroids through pressure-pulsed inhalation as treatment option of chronic rhinosinusitis with olfactory disorder. Patients with sinonasal olfactory disorder according to the European Position Paper on Rhinosinusitis and Nasal Polyps (EP3OS) were allocated to the new nasal inhalation therapy or a systemic corticosteroid therapy, each receiving a corticosteroid course of 12 days. 18 patients received topical corticosteroid pressure-pulsed inhalation (AMSA, Schumacher, Dausenau) and 15 systemic corticosteroid. Olfactory function was measured before and after treatment using the Threshold Discrimination Identification score (TDI score) and visual analogue scales. Lund Mackay score (LMS) was measured before starting treatment. Olfactory function (OF) increased from 17.5 ± 6.4 to 21 ± 7.9 TDI points (p \ 0.0005) after 2 months. OF decreased again to 19.5 ± 6.0 after 6 months (p = 0.007). OF increased from 17.0 ± 8.9 to 22.0 ± 9.5 points (p = 0.002) with systemic treatment after 2 months. In the follow-up period of 6 months, the mean TDI score dropped to 20.0 ± 9.2 points (p = 0.01). There was no correlation between LMS and TDI. Treatment of chronic rhinosinusitis with pressure-pulsed inhalation was demonstrated to be effective. Multicenter investigations with large participant numbers are needed.