Aim. Evaluation of the possibilities of a new semi-quantitative rapid test for procalcitonin in the diagnosis of multisegmental community-acquired pneumonia. Materials and methods. A one-stage comparative study involved 123 patients hospitalized in a hospital with a confirmed diagnosis of community-acquired pneumonia. The mean age of the patients was 49.5 +/- 21.0 (M +/- SD) years. On the first day of hospitalization, all patients underwent a general clinical examination, chest x-ray, and a plasma procalcitonin level was determined using a semi-quantitative rapid test. Results. Indicators of a new semi-quantitative rapid test for procalcitonin of at least 2 ng/ml are directly related to laboratory and instrumental indicators reflecting the severity of community-acquired pneumonia, namely, the severity of respiratory failure (p=0.001), respiratory rate (p=0.001), and heart rate contractions (p=0.001), systolic blood pressure (p=0.025), oxygen saturation (p=0,001), erythrocyte sedimentation rate (p=0.021), fibrinogen (p=0.003) and high CRB-65 scores (p=0.001). They are also associated with multisegmental community-acquired pneumonia (chi(2)=4.7; p=0.030) and complications of this disease, such as hydrothorax (p=0.029) and death (chi(2)=22.1; p=0.001). Conclusion. Using a new semi-quantitative rapid test for procalcitonin allows you to optimize the diagnosis of complications of community-acquired pneumonia and determine the high risk of multisegmental pneumonia.