A new genetic sexing strain of the Mexican fruit fly, Anastrepha ludens (Loew), was evaluated in tests of sexual behavior to determine its possible application using the sterile insect technique. Tests in field cages measuring time to sexual maturity, compatibility with wild flies, and competitiveness were compared between the genetic sexing strain, Tapachula-7, and the mass-reared standard bisexual strain. The results indicated that the onset of sexual maturity was similar for both laboratory strains. Males from the Tapachula-7 strain do not differ from the standard bisexual strain in compatibility and competitiveness with wild insects. The results indicate that the release of Tapachula-7 males in the field would be viable in programs that use the sterile insect technique for the control of the Mexican fruit fly.