The aim of the present research is to find out constraints English language teachers face in conducting CLT based activities at Secondary School Certificate (SSC) level in the rural areas of Pakistan and how much these constrains affect English language learning. The population for the present research consists of 20 teachers (male and female) of govt. and private schools of Tehsil Fort Abbas, District Bahawal Nagar. The data have been collected from the teachers through a semi-structured interview and a close-ended questionnaire. A semi structured interview of 05 teachers is conducted to take idea about their concept of CLT, its implementation and difficulties in conducting the CLT based activities. A close ended questionnaire consisting of 10 questions is designed on a 4-point Likert... scale to have an idea about the constraints in applying CLT in the classrooms and have been given to 20 teachers who are teaching at SSC level. The data collected have been analyzed qualitatively as descriptive analysis and quantitatively in the forms of graphs, tables, frequencies and percentages by using MS Office software. The findings show that the teachers face constraints in applying CLT like impact of mother tongue of the students, large size of class, shortage of time, poor supportive home environment, lack of interest and motivation, lack of oral examination. It is suggested that the teachers should work honestly and professionally to enhance the communicative competence of the students and the govt. should provide the basic facilities so that CLT can be carried out in a finer manner in the ESL classes.