The present invention relates to a microbicidal α-amino acrylic derivative and its preparation method and applications. Based on the principle of pesticide molecular design, the structural reform of the agricultural anti-plant virus activity is carried on lead compounds having the medical anti-coronavirus activity, and a series of α-amino acrylic derivatives are designed and synthesized, and in particular, α-amino acrylic derivatives containing piperidine rings are synthesized, and the systematic biological activity screening is carried by using known compounds as positive control compounds, which provide many effective anti-virus leading molecules for the preparation of pesticides, and has positive significance to reduce the pesticide application dosage and protect the environment and ecology.