In order to study the role of Picture Archiving and Communications Systems (PACS) in optimization of the "City Mariinsky Hospital" radiology department, economic and di-agnostic efficacy of PACS wereanalyzed taking into account the development of com-munications and the usage of image post-processing after the introduction into clinical practice of digital X-rays. The material of the study included: PACS system; radiographs to assess the impact of post-processing on the diagnostic efficacy; questionnaire survey of ra-diologists on the use of post-processing methods; Query analysis in X-ray and an electronic archive to estimate the time when the photo was taken, the comparative calculations of the costs for consumables to assess the economic feasibility of PACS. The following results: 1. The introduction of PACS and the transition to Digital X-ray are economically beneficial to health facilities meaning annual savings on the X-ray film and chemical reagents (about 3.19 million rubles). 2. In the context of the prospects for the optimal modification of fifteen PACS is a lucrative object of investment. 3. The time of the digital image receipt from elec-tronic archive by an average of 28 minutes shorter than the time of delivery of the X-ray film from X-ray archive. 4. The image post-processing significantly improves the accuracy of di-agnosis. 5. More than 70% of radiologists, physicians (83% of them) are performing post-processing of digital X-ray.