Objective: To evaluate relationship between skin prick test results and serum total IgE,C-reactive protein, body mass index in patients with allergic diseases.Material and methods: This study was conducted in university hospital between October 2011 and September 2018. Skin Prick test (SPT) was applied to 433 patients in chest diseases clinic who were referred with diagnosis of asthma, allergic rhinitis, chronic urticaria and atopic dermatitis. Also patients’ serum total IgE, C-reactive protein (CRP) levels and body mass index (BMI) measurements were evaluated.Results: The study group were consisted of 433 patients, 189 (43.6%) male, and 244[G1] (56.4%) female. According to the diagnosis, 177 (40.9%) patients had asthma, 108 (24.9%) had allergic rhinitis, 82(18.9%) had atopic dermatitis and 66 (15.2%) had chronic urticaria. SPT was positive in 285 (65.8%) patients while negative in 148(34.2%). Most frequently seen allergens were the mixture of trees 23.2%, home dust 19.2%, savage grass 14.8%. Total IgE, CRP, and BMI values were statistically higher in SPT positive group. (p[G2] ˂0.001). Obese patients had statistically significant positive skin prick results (p=0.036). Also, positive total IgE and CRP groups were significantly higher in positive SPT group (p ˂0.001 and p=0.008). There was a moderate level and significant positive correlation between total IgE levels and SPT (r=0.463, p˂0.001). Also CRP levels (r= 0.128, p=0.008) and obesity (r=0.101, p=0.036) had a low level and significant positive correlation with SPT. Only total IgE was the statistically significant risk factor for [G3] the SPT.[G4] Positive total IgE level increases the probability of positive SPT by 8.11 times. Conclusion: This study suggests that elevated levels of total IgE, CRP and obesity may have relationship with atopy by increased likelihood of positive skin prick test. Positive Total IgE level can be a strong predictor for skin prick test positivity.