This electroencephalography (EEG) study tested the benefits of generative learning and the underlying neural mechanism of these benefits when learning from video lectures. Twenty-six Chinese young adults independently viewed two video lectures in a repeated measures design. Each video lecture was broken into 40 segments, and after each segment, the participants either generated an oral sentence (generative learning condition) or viewed a sentence (passive viewing condition). Participants' learning performance (accuracy and reaction time) were assessed after viewing each video, and their EEG oscillations (i.e., lower alpha band and upper alpha band in frontal and occipital-parietal regions) were recorded while watching each video and while generating a sentence or viewing a sentence. Paired t tests showed that students had higher learning performance (higher accuracy and shorter reaction time) after learning by using a generative learning strategy than learning by passive viewing. Repeated measures ANOVAs showed that when learning by using a generative learning strategy, students exhibited increased frontal and occipital-parietal lower alpha and upper alpha power, both while watching the video lectures and generating/viewing a sentence. The two learning strategy conditions showed a larger difference in upper alpha power than in lower alpha power. Correlation analyses showed that students' alpha power in the generative learning strategy condition was positively related to their reaction time. Based on the learning performance tests, generative learning is more effective than passive learning from video lectures; based on the EEG results, the effectiveness appears to be due to students being primed to apply a top-down processing strategy. The findings have an important practical implication: instructors can encourage students to engage in generative learning after viewing video lectures.