The problems of high course selection rate, low completion rate, and insufficient pertinence of learning support services in online general education courses are the focus of current general education researchers. Based on 3P (presage, process, and product) learning theory, we put forward a “three-stage, four-level” framework for learners’ portrait process of online general education course, including three learning stages of “presage process product” and four levels of “portrait goal, data collection, label analysis, and portrait service.” Then, taking the learners of the online general education course of Zhejiang Shuren College as an example, we make a case analysis based on the portrait framework, evaluate the learning effect from different stages, and put forward targeted teaching strategies and measures. Research results show that the proposed framework can reflect the characteristics of online learning experience, online learning investment, and online learning results of high-risk learners and can provide data support for the design of online learning support services and optimizing learning effects.