What causes pain in the penis after urination?

Urethritis. Urethritis is inflammation of the the urethra (straw-like hollow tube in the penis). When the hollow tube in the penis is inflammed, there may be a sensation of burning / pain with urination. In some instances urethritis is caused by infections. These can be both sexually and non sexually acquired. Would be good to go to a clinic or doc to get this looked into. Hope that this helps.