Objectives: The purpose of this study was to investigate and compare the attitudes of English medium instruction (EMI) lecturers and students and non-EMI lecturers and students toward English in Algeria. The Algerian government plans to implement English as a medium of instruction in higher education. Methods: The research was carried out at an Algerian university where French is the primary language of instruction, but English is used as the medium of instruction for certain courses in the engineering department. Data were gathered through a questionnaire, which was distributed to a group comprised of 52 EMI lecturers, 226 EMI students, 70 non-EMI lecturers, and 254 non-EMI students in engineering programs. Additionally, 18 EMI lecturers, 18 EMI students, 18 non-EMI lecturers, and 18 non-EMI students were interviewed. Findings: Most participants hold a positive attitude toward English, with a slightly negative attitude among senior non-EMI lecturers. Educational, instrumental, and linguistic reasons were the main factors behind the participants' positive attitudes. Most Algerian higher education lecturers and students are aware of the high prestige of English and its importance in research and technology. On the other hand, some senior lecturers display negative attitudes, believing that English does not deserve its high prestige and status. Recommendation/Significance: In its implementation of EMI, the Algerian Higher Education Ministry should highlight English's eminence in the global community and underscore its advantages in the Algerian context. This could be accomplished by organizing workshops and training sessions that center on such benefits.