Aim - to explore the features of comorbidity and multimorbidity of infiltrative pulmonary tuberculosis (IPT), peptic ulcer (PU), HIV infection in modern conditions. Materials and methods. The study involved 392 patients with IPT aged 20-44 years, HIV-positive with CD4 200500/pl, suffering from uncomplicated ulcer. Results. Peptic ulcer disease was diagnosed in 20.5% of patients with IPT and 19.5% patients with HIV infection in stage C2 and IPT, complaining of dyspepsia. The multimorbid combination of IPT, HIV infection and PU is characterized by: oligosymptomatic onset of tuberculosis; the clinical picture shows the dominance of asthenic syndrome, manifestations of gastric and intestinal dyspepsia, weight loss (2-4 times more frequently than in patients without HIV infection), less prominent destructive process in the lung tissue (2 times less than in patients without HIV infection). H.pylori is the aetiological factor of PU in 62.5% of patients with IPT and 58.7% patients with HIV infection in stage C2 and IPT. The combination of H.pylori-negative PU and IPT has significantly more unfavorable prognosis compared to comorbidity of H.pylori-positive peptic ulcer and IPT. Conclusion. Diagnosis of PU, HIV infection and H.pylori-status allows defining multiple categories of comorbidity (patients with IPT and dyspeptic syndrome, patients with IPT and H.pylori-associated peptic ulcer, patients with IPT and H.pylori-negative ulcer) and multimorbidity (HIV-infected patients with IPT and H.pylori-associated ulcer, HIV-infected patients with IPT and H.pylori-negative ulcer).