Background <p>Anomalous systemic artery to the left lower lobe (ASALLL) is a rare congenital anomaly. The primary symptoms include hemoptysis and lung infection, though some patients may remain asymptomatic. Currently, there is no consensus on the indications for treatment or the optimal choice of therapy for this condition. This case presents a case of an asymptomatic adult who underwent coil embolization.</p> Case presentation <p>A 48-year-old male was admitted to our hospital due to the discovery of a space-occupying lesion in the left hilum. The contrast-enhanced pulmonary computed tomography scan was used to diagnose the patient with an anomalous systemic artery to the left lower lobe. We performed coil embolization on this patient, who underwent a follow-up computed tomography angiography of the pulmonary and bronchial arteries one year later. Result demonstrated complete embolization of the abnormal systemic arteries and a slight reduction in the volume of the left lower lobe.</p> Conclusion <p>Coil embolization is a safe and minimally invasive procedure for adult patients who have an anomalous systemic artery to the left lower lobe.</p>