Aim:The purpose of this study was to determine the host risk factors associated with mortality in COVID-19 patients who are hospitalized for pneumonia, and also, to find a COVID-19 mortality score based on these. Methods:All patients diagnosed as confirmed or probable COVID-19 pneumonia whom hospitalised in our Chest Diseases Education and Research Hospital between March 11, 2020 and October 1,2020 were enrolled. The optimal cut-off values, sensitivity and specificity values and odds ratios to be used in mortality prediction of the novel scoring system created from these parameters were calculated by ROC analysis according to the area under the curve and Youden index. Results:Over 422 patients (n: 51 mortal, n: 371 survivors) univariate regression analysis showed that age, male gender, smoking, comorbidity, and using ACE inhibitor were prognostic host risk factors for COVID-19-related mortality. Using this analysis, a novel scoring model Co-AMSCA (Age, Male, Smoking history, Comorbidity, ACE inh)was established. The cut-off value of this scoring system (including only host risk factors), which determines the mortality risk in patients, was 3.5 points with 88.4% sensitivity and 65.5 % specificity (AUC = 0.761, 95% CI 0.697-0.826, P < .001) (Figure 1). The mortality risk in patients with a Co-AMSCA mortality score above 3.5 points was 7.8 times higher than patients with lower than 3.5 (OR= 7.8; P < .001).In multivariate logistic regression analysis, older age and smoking (smoker/ex-smoker) were found to be important risk factors for mortality (OR = 12.09; 95% CI 2,564-57,054 P =0.004 and OR = 3.1; 95% CI 1,381-7,295; P = 0.007,respectively). Counclusion:We created a simple mortality score, which is easily calculated and does not require laboratory and time.This study showed that by using Co-AMSCA mortality score that has only host risk factors achieved a prediction of mortality in COVID-19 patients who are hospitalized for pneumonia.