Objective To explore the correlation between ostiomeatal complex(OMC)variation, nasal septum deviation and nasosinusitis with CT imaging.Methods The clinical and imaging data of 256 patients undergoing nasal and paranasal CT examination from June 1, 2015 to May 30, 2016 were retrospectively analyzed. Patients with paranasal sinus fractures, tumors and artifacts were not included in this study.Taking the image of standard coronal MPR built with thin axial sections at the level of middle of semilunar fissure as observing image,and the direction,location and extent of OMC variations were observed and recorded. The patients were divided into two groups according to the presence or absence of nasal septum deviation.OMC mutation,the incidence of unilateral mutation,incidence of paranasal sinusitis and the incidence of unilateral bilateral nasal sinusitis between the two groups was analyzed by χ2test with two independent samples. Then according to the presence or absence of OMC mutation, the patients were divided into two groups.The incidence of paranasal sinusitis and bilateral paranasal sinusitis were compared between the two groups. Results Two hundred and fifty six cases of CT imging of parannasal sinus were included in the study,96 cases were with nasal septum deviation, 160 were with non-deviation of nasal septum. The incidence rate of OMC variation between the two groups showed significant difference(χ2=38.40,P<0.05).The incidence rate of unilateral and bilateral OMC variation showed significant difference(χ2=13.70,P<0.05),among which 54 were unilateral variations,50(92.6%)variations were located at the same side of nasal deviation(side of the nasal cavity widened).The incidence rate of sinusitis between the two groups showed non-significant difference(χ2=0.50,P>0.05).The incidence rate between unilateral and bilateral nasosinusitis showed non-significant difference(χ2=2.25,P>0.05).Of the 256 cases,128 were with OMC variations,and 128 were with non-OMC variation.The incidence rate of nasosinusitis between the two groups showed non-significant difference(χ2=0.56,P>0.05). The incidence rate between unilateral and bilateral nasosinusitis showed non-significant difference(χ2=3.57,P>0.05). Conclusion Ipsilateral OMC variation occurred in nasal septum deviation might be a compensation to nasal cavity widening while not a obstructive factor in causing nasosinusitis.