Mark J. Mazur is an American economist who formerly served as Assistant Secretary for Tax Policy in the U.S. Department of the Treasury.

[1][2][3] Mazur early worked as a tax accountant for General Motors before spending four years teaching public finance at Carnegie Mellon University.

Later, he entered government, working first as a staff member on the U.S. Congress' Joint Committee on Taxation and, later, in several middle management positions at the White House and the U.S. Department of Energy.

He eventually moved to the Internal Revenue Service where he was appointed to the senior-level position of director of research, analysis, and statistics of income.

He was named Assistant Secretary for Tax Policy in 2011, being confirmed to the post by the U.S. Senate the following year.