Disclosed is a stable pharmaceutical solution formulation of a GLP-1R antibody fusion protein, comprising a therapeutically effective amount of the GLP-1R antibody fusion protein, an amino acid, a surfactant and a buffer system. The final concentration of the amino acid is 1-500 mM, the final concentration of the surfactant is 0.01%-0.5%, and the pH value of the stable solution formulation is from 5.0 to 8.0. The stable solution formulation of the present invention can be used in the treatment of diabetes, obesity and conditions associated therewith.