Pulmonary actinomycosis (PA) is an uncommon, asymptomatic, and frequently misdiagnosed pulmonary infectious illness. Our patient remained undiagnosed despite extensive regular and invasive testing, significant intermittent hemoptysis, and repeated bronchial artery embolization. Ultimately, a left lower lobectomy was performed via video-assisted thoracoscopic surgery, and a histopathological examination revealed an actinomycete infection.