Sergeant Major Devon A. Fischer was born February 22, 1979 in Giessen, Germany. He enlisted in the Marine Corps July 2006 and underwent recruit training at Marine Corps Recruit Depot Parris Island, South Carolina. Upon graduation, he reported for training to Delta Company, ITB Camp Geiger NC. Upon Graduating ITB he was assigned to 1st Battalion 8th Marines as a Rifleman where he was meritoriously promoted to the rank of Lance Corporal. While assigned to Alpha Company Lance Corporal Fischer participated in Operation Iraqi Freedom from September 2007 to March 2008 in Ar Ramadi. Upon return from deployment LCpl Fischer was meritoriously promoted to the rank of Corporal and again deployed with Alpha Company in April 2009 to September 2009 to Iraq.

In January 2010 Cpl Fischer attended Marine Corps Basic Security Guard School in Chesapeake VA, for duties as a Basic Security Guard. Upon graduation of Security Guard School Cpl Fischer was assigned to 2nd FAST Company Yorktown VA, as Squad Leader. While assigned to 2nd FAST Sgt Fischer deployed from July to September to Bremerton Naval Shipyard Washington State. In December 2010 to July 2011 Sgt Fischer was deployed to Japan where he participated in Operation Tomodachi. Upon return from deployment Sgt Fischer was assigned as Platoon Sergeant and redeployed from September 2011 to November 2011 to Portsmouth Naval Shipyard Maine. Upon return from deployment Sgt Fischer was assigned as Regimental Chief Martial Arts Instructor Trainer where he completed eight Martial Arts Instructor Courses. In 2013 Sgt Fischer was meritoriously promoted to the rank of Staff Sergeant.

In July 2013, SSgt Fischer received orders to 1st Battalion 7th Marines Company B as rifle platoon sergeant where he participated in Operation Enduring Freedom from March 2014 to September 2014 in Afghanistan. After redeploying from Afghanistan SSgt Fischer was assigned as weapons platoon sergeant for Company B which is a billet reserved for a Gunnery Sergeant. From October 2015 to April 2016 SSgt Fischer redeployed in support of SPMAGTF 16.1. Upon return from deployment SSgt Fischer received orders to 1st MAW G3 were he was assigned as the SNCOIC for the Marksmanship Training Unit. On April 2, 2017 SSgt Fischer was meritoriously promoted to the rank of Gunnery Sergeant, and assigned as the 1st MAW Ground Training Chief and was part of the Commanding General's Inspection Team. Gunnery Sergeant Fischer received orders in 2019 and reported to Marine Corps Security Force Battalion Bangor WA. Upon arrival to the Battalion, he was assigned to the billet of H&S Co. First Sergeant for 14 months. In July of 2020 he transferred to A. Co where he served as operations chief. In May of 2021 First Sergeant Fischer was frocked and assigned to Det-1, MT Co.,CLB-453 Texarkana, Texas as the I-I 1stSgt until his selection to SgtMaj. In July 2024 he was transferred to Headquarters And Service Battalion 2nd MLG Camp Lejeune and assumed his current post as the Battalion Sergeant Major.

SgtMaj Fischer's personal awards include the Navy Commendation Medal (with 3 gold star), Navy Achievement Medal (with 3 gold stars), Combat Action Ribbon, Humanitarian Service Medal, and Military Outstanding Volunteer Service Medal. He graduated Cum Laude from the American Public University with a BS in Legal Studies, a Masters Degree in Public Administration from Troy University, and a Graduate Certificate in Sports Management from Liberty University. He is married to Nicole and they have one daughter Ciara and one son Devon Jr.