Squamous cell carcinoma of the penis is most frequent in uncircumcised men. Other contributing factors include human papillomavirus infection, phimosis, balanitis, and smoking. We present a patient, circumcised at birth, who showed penile squamous cell carcinoma in situ and was treated with carbon dioxide laser ablation. Squamous cell carcinoma rarely presents in patients circumcised as infants. Factors contributing to chronic inflammation may predispose to this disease. Carbon dioxide and neodymium:YAG lasers are two modalities that are successful in the treatment of in situ and probably early invasive penile carcinoma. Optimal treatment includes coordination with a urologist if urethral disease is present.