Objective To investigate the expressions of substance P (SP) and its receptor neurokinin/tachykinin receptor 1 (NK1R) in peripheral blood eosinophils of patients with psoriasis. Methods The levels of SP and NK1R in the peripheral blood of both patients with psoriasis and healthy people were detected by flow cytometry. This method was again used to detect the levels of SP and NK1R in the peripheral blood eosinophils of patients with psoriasis after stimulated with the crude extracts of Artemisia pollen, dust mite and Platanus pollen (all at concentrations of 0.1 and 1.0 μg/mL). Results Compared with the healthy controls, the percentages of SP+ and NK1R+ eosinophils in psoriasis patients increased up to 2.7 and 0.5 folds, respectively. Moreover, the mean fluorescence intensity (MFI) of SP+ and NK1R+ eosinophils of psoriasis patients were elevated by 1.5 and 0.2 folds, respectively. The percentage of SP+ eosinophils in psoriasis were down-regulated by 60% after the stimulation with Platanus pollen extract (1 μg/mL), while 0.1 μg/mL Platanus pollen extract induced a 0.6-fold increase in the percentage of NK1R+ eosinophis. Conclusion The expressions of SP and NK1R are up-regulated in peripheral blood eosinophils of patients with psoriasis.