Disclosed are PEG-modified Exendin-4 analogs and uses thereof. In particular, disclosed are PEG-modified Exendin-4 analogs as shown in formula (I), i.e., PEG-M-X-(Ex-4), or pharmaceutically acceptable salts thereof, as well as Exendin-4 analogs as shown in formula (II), i.e., [Aa p ]Exendin-4, wherein the symbols are as defined in the specification. Further disclosed are methods for preparing PEG-modified Exendin-4 analogs, uses of PEG-modified Exendin-4 analogs, compositions comprising the same, as well as use of the Exendin-4 analogs in the preparation of the PEG-modified Exendin-4 analogs. In the PEG-modified Exendin-4 analogs, modification by polyethylene glycol occurs in a site-directed manner in the peptide chains of the Exendin-4 analogs. The PEG-modified Exendin-4 analogs can be used to prevent and/or treat diseases and/or symptoms related to decreased activity of GLP-1 receptors, such as type II diabetes.
