Angiogenesis, the growth and proliferation of new blood vessels, is important in a variety of pathophysiological processes. However the role of angiogenesis in allergic rhinitis has not been well studied. Hence, the aim of this study was to compare the vascularisation of the nasal mucous membrane of non-allergic, non-treated allergic and allergic patients treated with mometasone furoate. A small piece of the nasal mucous membrane was taken from the frontal pole of the lower nasal shell from 90 patients. The patients were divided in three groups, each containing 30 patients. First group of patients (GP1) had a negative inhalatory allergen test, patients in second group (GP2) had positive test but were not under treatment and the third group of patients (GP3) had positive results with the same test and were treated with mometasone furoate for 15 days before analysis. Immunhistochemical staining with anti-CD31 and VEGF-C was performed. Vascular phase was determined by using length density. Differences in expression of CD31 and VEGF-C were compared using one-way ANOVA and Tukey HSD post-hoc tests. Significantly lower values of CD31 and VEGF-C expression were observed in GP1 in compare with GP2 and GP3 (p < 0.001, p = 0.013, resjpectively). In GP3 the microvessel density was significantly lower than in GP2 (p < 0.001), but higher than in GP1. Our results demonstrated that 15-day treatment with mometasone furoate results in a significant reduction of the density of vascular parameters in allergic patients.