Infectious laryngotracheitis virus (ILTV) is an alphaherpesvirus that causes severe and economically significant respiratory disease in poultry worldwide. Herein, the immunogenicity of two recombinant fowlpox viruses (rFPV‐gB and rFPV‐gB/IL18) containing ILTV glycoprotein B (gB) and chicken interleukin‐18 (IL‐18) were investigated in a challenge model. One‐day‐old specific‐pathogen‐free chickens were vaccinated by wing‐web puncture with the two rFPVs and challenged with the virulent ILTV CG strain. There were differences in antibody levels elicited by either rFPV‐gB/IL18 or rFPV‐gB as determined using ELISA. The ratios of CD4+ to CD8+ in chickens immunized with rFPV‐gB/IL18 were higher (P < 0.05) than in those immunized with rFPV‐gB, and the level of proliferative response of the T cells in the rFPV‐gB/IL18‐vaccinated group was higher (P < 0.05) than that in the rFPV‐gB group. All chickens immunized with rFPV‐gB/IL18 were protected (10/10), whereas only eight of 10 of the chickens immunized with the rFPV‐gB were protected. The results showed that the protective efficacy of the rFPV‐gB vaccine could be enhanced by simultaneous expression of chicken IL‐18.