Abstract: The present disclosure belongs to the field of biomedicine. Specifically, the present disclosure relates to a circular RNA molecule, a cyclization precursor RNA molecule, a recombinant nucleic acid molecule, a recombinant expression vector, a recombinant host cell, a composition and use thereof in targeted degradation of a protein of interest, as well as a method for preventing or treating a disease. The circular RNA molecule has good membrane permeability, is easily delivered into cells, and has high-efficiency in vivo protein targeted degradation activity. The circular RNA molecule of the present disclosure successfully achieves inhibition of tumor growth, which proves the in vivo protein degradation activity of bio-PROTACs for the first time, and provides a positive and effective treatment solution for the treatment of diseases such as tumor.