A patient, 22-year-old man, with a history of oral-genital sexual contacts had a peeled-off lesion on the body of the penis 7 days before hospital examination. He's been self-treated but no improvement has been seen. Patient visited at the National Hospital for Dermatology and Venereology with the injury of the 3-cm scarlet peeled-off lesion, clear boundaries. The lesion surface was covered with a little white pus and he was diagnosed of genital ulcers. He was tested for herpes PCR, chlamydia PCR, direct microscopy for H. ducreyi, T. pallidum, and culture for gonorrhea. Results: N. gonorrhoeae has been seen in the penis lesion and not in the urethra, throat, anus. Other tests were negative. Patient has been treated with Ceftriaxone 1 g-single intramuscular dose for 5 days but there was no change in the lesion, N. gonorrhoeae was still seen. Then patient was treated with cefixime at 200 mg/day for 7 days. Lesion progressed well and cured. Gonorrhea in the skin is rare. This case did not respond to the treatment of ceftriaxone. Genital ulcer lesions should be assigned additional tests for gonorrhea in order to avoid missing the diagnosis.