Avian Influenza Virus (AIV) has been prevalent worldwide in recent years, resulting in substantial economic losses in the poultry industry. More importantly, AIV is capable of cross-species transmission among mammals, posing a dormant yet considerable threat to human health and safety. In this study, two rapid detection methods for AIV based on the CRISPR-Cas13a were developed. These methods can identify AIV through the M gene and differentiate the H5, H7, and H9 subtypes via the HA gene. The first method utilizes RT-RAA isothermal amplification of the target sequence in combination with the “collateral effect” of the Cas13a protein. The results are measured using a real-time quantitative PCR instrument, with a Limit of Detection (LOD) as low as 1 copy/μL. The second method combines RT-RAA with Cas13a and a lateral flow assay, allowing results to be visually observed with the naked eye, with a LOD of 10 copies/μL. Both methods demonstrated specificity and sensitivity comparable to or exceeding that of qRT-PCR, suggesting strong potential for clinical application.