1. An automatic measurement system for plant features, comprising: a photographic device, for respectively photographing a plant in a container at different times, so as to generate a top view image and a side view image; and an operation processing device, electrically connected to the photographic device, and at least comprising an image processing module and a storage unit, wherein the image processing module analyzes at least one of the top view image and the side view image corresponding to the different times by using an image processing procedure and an analysis rule, so as to generate a feature data corresponding to appearance features of the plant, and records the feature data in the storage unit, and the operation processing device further generates at least one selected from a group consisting of a recording report, a plant growth analysis, and a plant growth history corresponding to the plant in the container according to the feature data corresponding to the plant in the container at the different times by using the plant record processing procedure.