The Elf5-Cre mice were constructed using gene editing technology to insert the P2A-Cre expression element into the endogenous Elf5 gene of mice. The expression pattern of Cre recombinase is similar to that of the endogenous gene. When this strain is crossed with mice containing loxP sites, sequence recombination between loxP sites mediated by Cre recombinase can occur in tissues such as the mammary gland and uterus of offspring mice. The heterozygotes are viable and fertile.