Sergeant Major Jose Romero was born in San Antonio, Texas and graduated from Sidney Lanier High School in 1998. He then enlisted into the United States Marine Corps and attended recruit training aboard Marine Corps Recruit Depot, San Diego, CA. Upon graduation as a Private from recruit training, he attended Marine Combat Training (MCT), Camp Pendleton, CA. After completion of MCT, he then reported to Camp Johnson, NC for the enlisted Supply Basic Course, graduating as a 3043 Supply Administrator.

In March 1999, Private First Class Romero reported to 1st Marine Division, 1st Tank Battalion in Twenty-nine Palms, CA. There he was meritoriously promoted to the rank of Corporal. In December 2002, Corporal Romero reported to 1st Marine Aircraft Wing, in Okinawa, Japan where he was assigned to Marine Air Control Squadron 4.

In September 2003, Corporal Romero reported to 8th Marine Corps District, Recruiting Station San Antonio, TX where he served as the Supply NCO and Color Sergeant. There he was promoted to the rank of Sergeant. In October 2005, Sergeant Romero reported to Drill Instructor School at Marine Corps Recruit Depot San Diego, CA and served as a Drill Instructor and Senior Drill Instructor in First Recruit Training Battalion, Company A. He was then promoted to the rank of Staff Sergeant and served as the 1st Battalion Drill Master.

In January 2009, Staff Sergeant Romero reported to 2d Marine Division, 1st Battalion, 9th Marines, Camp Lejeune, NC. He was assigned to Headquarters and Service Company and served as the Supply Chief, he deployed on the 24th Marine Expeditionary Unit (MEU) aboard the USS Nassau and contributed to the relief efforts in support of Operation Unified Response in Port-au-Prince, Haiti, and in the Republic of Djibouti, in the Horn of Africa, and also, in Combat Operations in Southern Trek Nawa, Afghanistan in support of Operation Enduring Freedom (OEF). In May of 2012, Gunnery Sergeant Romero reported to 8th Marine Corps District, Recruiting Station Dallas, TX where he served as the Supply Chief.

In June 2014, First Sergeant Romero reported to 3d Marine Division, 2d Battalion, 3d Marines, and served in Company G, Headquarters and Service Company, and The Weapons Company in Kaneohe Bay, HI. He deployed in support of the Pacific Forward Deployed Forces and also served as the Senior Enlisted Leader aboard the USS Germantown. He executed bilateral amphibious, jungle and urban training and operations, promoted cooperation and interoperability between U.S. forces and Indonesia, Malaysia, Thailand, and the Philippines as the Landing Force Cooperation Afloat Readiness and Training.

In November 2017, First Sergeant Romero reported to 3d Marine Aircraft Wing, 3d Low Altitude Air Defense Battalion (3d LAAD Bn), and served as the First Sergeant for Headquarters and Service Battery in Camp Pendleton, CA. In September 2018, Sergeant Major Romero reported to Marine Air Support Squadron 3, and served as the Squadron Sergeant Major. In May 2019, Sergeant Major Romero reported to 3d LAAD Bn as the Battalion Sergeant Major. In February 2021, Sergeant Major Romero reported to 1st Marine Logistics Group, Combat Logistics Battalion 13 (13th MEU) as the Battalion Sergeant Major. He deployed on the 13th MEU aboard the USS Makin-Island in support of the Indo-Pacific. In September 2023, Sergeant Major Romero reported to Training Command, Marine Aviation Training Support Group 22 in Corpus Christi, TX.

Sergeant Major Romero's personal awards include the Meritorious Service Medal (gold star in lieu of second award), the Navy and Marine Corps Commendation Medal (silver star in lieu of six award), the Navy and Marine Corps Achievement Medal (two gold stars in lieu of third award), and the Military Outstanding Volunteer Service Medal (bronze star in lieu of second award).