English language is the official language in Nigeria. Successive governments have constantly invested both human and material resources to improving literacy especially in the North Eastern Region of the country where Adamawa state belongs. This research sought to identify and evaluate the factors necessary for a decline in the performance of senior secondary school students in English Language. The research believes that the performance level depends greatly on what happens in the process of teaching and learning the English language. The study using focal discussion groups identified mubi Educational Zone as one of the key Educational Zones in Adamawa State. Drawing on the tenets of skimmer theory, schools, teachers and students were selected as respondents to identify the factors responsible. Mean and statistical tables were used to derive the average score and effect of the identified factors on teaching and learning of the English Language. The study identified school environment, class size, students’ interest, teaching methods and teachers’ qualification as factors responsible for poor performance.