Immune checkpoint inhibitors, now FDA-approved, are being increasingly used for diverse cancer types. Dermatological complications are most frequent immune-related adverse events during immune checkpoints inhibitors therapies. There is no case reporting psoriasis exacerbation from Asia until now. We present a case of a 53-year-old Chinese man with non-small cell lung cancer (NSCLC) who presented with severe psoriasis at about two weeks after atezolizumab initiation. A skin punch biopsy was performed which revealed these were hyperkeratosis with IL-17A expression positive and confirmed the diagnosis of psoriasis. Atezolizumab was discontinued. Psoriasis was treated with flumethasone ointment every 12 hours and desloratadine 5 mg once daily for 2 weeks instead of phototherapies and improved completely over the next 2 months. He received chemotherapy in 4 cycles and radiotherapy and remained stable disease until December, 2019. Oncologists should pay attention to potential psoriasis exacerbation when patients use anti-programmed death ligand 1 (anti-PD-L1), especially who had a personal psoriasis-related history.