The present invention relates to the field of biopharmaceuticals, and in particular to a protein, a protein conjugate, a pharmaceutical composition and its use for treating diabetes. The fusion protein of the present invention is obtained by linking two polypeptides, wherein one polypeptide is an interleukin-1 receptor antagonistic protein or an analogue thereof, and another polypeptide is GLP-1 receptor binding polypeptide or an analogue thereof, or an insulin receptor binding polypeptide or an analogue thereof, or a GIP receptor binding polypeptide or an analogue thereof. The fusion proteins of the present invention and conjugates thereof have a significant efficacy in treating diabetes, and can be used in a lower dose, resulting in marked reduction in side effects.
