This style of men's hair cut is called a brush cut, buzz cut or crew cut.
crew cut definition by Webster's New World
Webster's New World College Dictionary Copyright © 2010 by Wiley Publishing, Inc., Cleveland, Ohio. Used by arrangement with John Wiley & Sons, Inc.
a style of man's or boy's haircut in which the hair is cropped close to the head, but left bristly on top to look like a brush
crew cut - Phrases/Idioms
A closely cropped haircut, usually for a male, as in The boys all think crew cuts are cooler in summer. This term presumably originated in the navy (crew referring to a ship's crew), where such a haircut was mandatory. [c. 1940]