Q. Can a man wear a wig?

A. If the wig is a man’s hairpiece it is permitted (Yalkut Yosef – Kisui Harosh 2: 23, Lebush Malchus 2, Chashukei Chemed – Bava Kama p.445, Nishmas Avrohom 3 p.76 in regards to covering one’s head).
However, if the remaining natural hair of the man using the wig is of white color and he wants to wear a dark colored wig Kedushas Yisroel (p. 88) forbids because of the prohibition of Lo Yilbash.
Horav Shlomo Miller’s Shlit”a opinion is that if it is the black color that most women would not choose for a wig, it is permitted.

Rabbi A. Bartfeld as revised by Horav Shlomo Miller Shlit”a