Semen of broiler breeder males was collected and used for artificial insemination. Semen was used undiluted and diluted and both inseminated immediately after collection. Only diluted semen was used after storage. Half of the semen samples to be stored were first dialyzed. Storage of fresh, diluted semen was for 4 or 24 h at 5 C or by cryopreservation. The Beltsville Poultry Semen Extender was used for dilution and dimethylsulfoxide (DMSO) was used as cryoprotectant. Fertilizing ability was determined as the percentage fertilized eggs of eggs collected from Day 2 to 17 after a single insemination. Dialysis had a small positive effect on fertilizing ability of semen stored for 24 h. Dialysis before cryopreservation did not improve fertilizing ability. The effects of storage for 4 h were only apparent in eggs collected 9 or more d after insemination. Semen stored for 24 h gave reduced fertilizing ability in the 1st wk after insemination, especially when no dialysis was applied.