This paper first studied the association rule algorithm model’s mining steps and algorithm features and improved the algorithm by quantifying attributes and frequent clustering. Then, the “Internet +” English teaching scheme for agricultural majors is proposed, the corresponding teaching system is designed, and a fresh approach to teaching English is developed. The impact of the teaching reform was evaluated using the indices of English efficiency, ability change, and learning status. The mean values of students’ learning attitude, interest, strategy and efficiency increased by 0.299, 0.844, 0.522 and 1.074, respectively, after using the “Internet + Classroom” teaching mode, which indicates that the new English teaching mode has significant teaching effects. This study provides new ideas and practical experience for reforming English courses in agriculture.