Citrus production is threatened by Huanglongbing disease transmitted by Asian citrus psyllid, Diaphorina citri Kuwayama. Developing strategies to control the vector is necessary. Conidial infectivity of four Mexican strains of Hirsutella citriformis Speare (INIFAP-Hir-2, INIFAP-Hir-4, IB-Hir-1, and IB-Hir-2) was evaluated in a semifield bioassay against adult Asian citrus psyllid. The bioassay was done in an orchard of Persian lime (Citrus aurantiifolia (Christm. et Panz.) Swingle var. latifolia Yu. Tanaka) at Veracruz, Mexico. The four strains showed pathogenicity, but INIFAP-Hir-2 and INIFAP-Hir-4 killed most (51.05-50.6%), with no significant difference between them. Thirty days after application in the field, several H. citriformis strains were recovered from mycosed insects and grown in different media where they varied depending on the culture medium and strain and presented morphological characteristics similar to the strains applied and to a local strain previously isolated. Mycosed insects increased from 2.3 to 10.0 per tree 30 days after application of strains of H. citriformis in the orchard. The four H. citriformis strains applied by spraying showed pathogenicity against the Asian citrus psyllid under semifield conditions. Entomopathogenic fungi such as H. citriformis could be a promising alternative in an integrated management program against Huanglongbing, but need more evaluation in the field.