I have a flat black spot on my penis shaft is this normal?

Normal for you: When it comes to skin the first question is if this is new or not. Is this an injury or not. Is it changing or growing? Skin issues are difficult to discuss and diagnose on the internet because this is such a visual field. Any good physician can tell you upon examination if you need to worry or not.

Need evaluation: This could be as simple as benign nevus or as complicated as a melanoma. Cannot make the call with just a comment but rather a thorough evaluation by your primary care physician, urologist or perhaps a dermatologist would be beneficial.

Get this checked.: A black mole is worth getting checked. Black, blue, gray, or multi-colored moles are more rare than pink or brown - and they are sometimes malignant. Be alert especially for changes in a mole: changes in the borders, itching or spontaneous bleeding. But get it checked out by your health care provider so you don't have to worry.

Usually is: A lentigo or two is common on a guy. Show your physician at your next regular physical exam, or if it starts to grow or ulcerates or develops a bump, get seen earlier.

Depends: If this is new, i would have it looked at by your doctor. It could be normal, but without looking at it, it is impossible to tell.