ABSOLUTELY! They have to have protection from the damaging rays just like everyone else does. They can, and do, get skin cancer just like every other race. The only difference is that they don't absorb as much Vitamin D and therefore need to have more supplement of it.
It is good for anyone to wear sunscreen. African Americans have more melanin in their skin so they can be more at risk for many different skin disorders and disease.
African Americans don't need to wear sunscreen because of the rich levels of melomine in their skin.