I have a fishy smell on my penis, what can it be?

Yeast infection: The most common cause is a yeast infection. The medical term, balanitis, means inflammation of the end of the penis (the glans). The most common cause is a yeast infection called candidiasis, also know as thrush. It develops under moist skin fold areas like the foreskin. An anti fungal cream like lotrimin (clotrimazole) will usually take care of it. If not or if swollen/ painful see md. Good health.