The study examines the relationship between language of instruction and students’ performance in financial accounting subject in North east, Nigeria. The study is quantitative and uses a sample of 250 financial accounting subject teachers in secondary schools within the Northeast Nigeria. Regression analysis was conducted using SPSS version 25. It was found that, language of instruction and teachers’ selectivity of words positively influence students’ performance in financial accounting subject in the region. Based on the findings, the study concludes that school officials should among other things ensure that instructors are properly nurtured on effective communication skills. The education policy makers in the Northeast states are enjoined to encourage their respective governments on the need to adopt language of the community as the medium of instruction for financial accounting in senior secondary schools. Governments of the states should through the Ministry of Education regularly build the capacity of accounting teachers on the language of instruction to enhance language proficiency and provide better communication that promotes understanding of students in financial accounting subject. Also, both school management and parent should encourage the students to develop the attitude of speaking and interacting with each other in the language of instruction to enable them to master the language and perform better in financial accounting subject.