Actinomycosis is a rare, chronic infectious disease caused by anaerobic Gram-positive bacteria Actinomyces spp. They induces suppurative inflammation in tissues. They live as commensals in the oropharynx, interstitial tract and genital mucosa, causing almost exclusively endogenic infections. Beacause variable clinical course, its chronicity, quite often actinomycosis mimics rather neoplasmatic disease than infection. We present the case of 56-year old male with unusual pulmonary actinomycosis manifestation as bilateral disseminated lung nodules with systemic symptoms, after initial antitubercular treatment. Diagnosis definitely was made of histologic evaluation of lung specimen from surgical biopsy. After 7-month antibacterial treatment we have achived clinical and radiological improvement.