The invention provides a cloud image coding method based on an object library and aims to solve the technical problem that the number of coded bits of a cloud image in the prior art is large. The method comprises the following steps: carrying out object detection on a to-be-coded cloud image; acquiring an object database; searching and matching the cloud object image obtained by carrying out object detection on the to-be-coded cloud image and the object image in the object database to obtain a candidate coded reference object image set (formula); screening the candidate coded reference objectimage set (formula) to obtain a coded reference object image set; finally, using the object image in the coded reference object image set as a coded reference image to carry out HEVC coding on the to-be-coded cloud image. The method can be applied to the fields of internet cloud image compression, personal photo album compression and the like, and compression coding is carried out on the to-be-coded cloud image.