Frank J. Grass (born 19 May 1951) is a retired United States Army general who served as the 27th chief of the National Guard Bureau.

[5] He joined the Missouri Army National Guard in October 1969,[6] and served as an enlisted soldier and noncommissioned officer before graduating from Officer Candidate School in 1981 and receiving his commission as a second lieutenant in the Engineer Corps.

[10] In June 2012, Grass was nominated by President Barack Obama to serve as Chief of the National Guard Bureau, with appointment to the rank of general in the reserves of the army.

[12][13] In 2016, the Vice Chief of the National Guard Bureau, Joseph L. Lengyel, was nominated to succeed Grass.

Lengyel was promoted to general and completed a transfer of authority ceremony with Grass on 3 August 2016.