Due to the increasingly serious problems of environmental pollution and resource waste, promoting the green and low-carbon transformation of education has become a new trend. Online foreign language education is a new mode of green transformation development relying on digital technology. Based on the new background of green technology, this paper focuses on the evaluation of online foreign language teaching satisfaction and the key influencing factors. The entropy weight method was used to construct the evaluation index of online foreign language teaching satisfaction, the multiple linear regression model and confirmatory factor analysis model were used to systematically analyze the main factors affecting the satisfaction, and the questionnaire was used to investigate the data of online foreign language courses such as American Literature, American Culture, College English, Comprehensive English, and History of Foreign Literature. The results show that: (1) college students have a high degree of satisfaction with online foreign language teaching, and the satisfaction index based on entropy weight method is above level 2. (2) Through the multiple linear regression model, the four dimensions of teaching involvement, teaching communication, teaching skills and teaching effect all have a significant impact on the satisfaction of online foreign language teaching. (3) Based on the confirmatory factor model, online foreign language teaching satisfaction is affected by multiple latent and explicit variables, and the effect direction is generally positive. Finally, the paper puts forward specific strategies to improve the effect of green and low-carbon digital technology on foreign language education.