Born in 1927 in a labor camp near Los Banos, California, Padilla was a child of migrant farm workers who traveled with his family throughout California, where they picked cotton, tomatoes, and fruit. He later served in the U.S. Army, earning many commendations.
In 1955, Padilla met Chávez, then an organizer for the Community Service Organization (CSO), at a meeting at Padilla's home in Hanford, California. For the next seven years, Chávez and Padilla worked together in the CSO, where Padilla served as a volunteer from 1955 to 1960 then as a staff member until 1962, conducting citizenship classes and voter registration drives, and engaging in many activities to gain rights for farm workers and others in need. When Chávez left the CSO in 1962 to begin organizing a farm workers' union, Padilla joined him. At the first UFW (known then as the National Farm Workers Association) conference in September 1962, Padilla was appointed an area director. During the next two years, he and Fred Ross, funded by Saul Alinsky and the Industrial Areas Foundation, worked to organize service centers throughout the state of California.
For 18 years, Padilla helped build the UFW, serving as secretary-treasurer from 1973 until 1980. He led union membership drives in California and Texas and participated in boycotts in Philadelphia and Washington, D.C. Notably, in the fall of 1965, he and his family moved to Delano, California, so that he could work full-time on the Delano grape strike; in 1967, the union sent him to Rio Grande City, Texas, where he organized boycott committees throughout the state in support of the strike against Las Casitas Farms.
After a disagreement with Chavez and UFW board members over the direction in which the union was headed, Padilla left the UFW in 1980 for a variety of jobs in political and social work. For a time he was president of the Fresno Civil Service Commission. In 2005, he joined other CSO veterans in a project to document and pass on the lessons that empowered the organization's community organizing efforts.
Pawel, Miriam. The Union of Their Dreams: Power, Hope, and Struggle in Cesar Chavez’s Farm Worker Movement. New York: Bloomsbury, 2009; Padilla, Gilbert. "Gilbert Padilla 1962-1980." Farmworker Movement Documentation Project (http://farmworkermovement.com/essays/essays/005%20Padilla_Gilbert.pdf).