Despite advances in the diagnosis and treatment of pneumococcal infections, effective antibiotic therapy for pneumococcal pneumonias remains to be a topical problem. The investigation was undertaken to study the specific features of development of antibiotic resistance in S. pneumoniae strains isolated in patients with pneumococcal pneumonias. In the Primorye Territory, pneumococcal pneumonia mortality rates were established to be 32.73 +/- 1.58 (28.98-36.48) per 10,000. At the same time the major portion of drug-resistant strains was those that were resistant to trimetroprim- sulfamethoxazole (52.34%), tetracycline (58.4%), clindamycin (32.88%), erythromycin (12.08%), and ciprofloxacin (12.75%). The increase in the number of pneumococcus strains resistant to macrolides and fluoroquinolones in the age group of 5 to 18 ages allows one to recommend that the use of drugs of these groups be improved first of all in patients of this age who have invasive forms of pneumococcal infections.