Recent studies indicate that anti-tumour necrosis factor (TNF) antibodies may cause psoriasiform skin lesions in a subgroup of anti-TNF-treated patients with inflammatory bowel disease (IBD). This side effect seems to be paradox given that TNF-α plays a key role in the pathogenesis of psoriasis and anti-TNF inhibitors are used for the treatment of severe psoriasis. The estimated prevalence of psoriasis in IBD patients receiving anti-TNFs are 0.6-5.3% with variations in previous studies. Herein, we report a rare case of psoriasis associated with anti-TNF- α therapy in a patient with inflammatory bowel disease. A 42-year-old woman presented with pruritic, multiple erythematous scaly plaques on the whole body for 2 years. The patient was diagnosed with ulcerative colitis (UC) five years ago and for treatment, she had received intravenous infliximab injection every two months for 3 years. A skin biopsy specimen showed typical psoriasiform change in the epidermis. Based on clinical manifestation and histopathology, the patient was diagnosed with psoriasis induced by the infliximab injection. After one month of treatment with topical agents (calcipotriol, betamethasone) and oral antihistamines, the skin lesion was much improved and she is under the close follow up.