This study was carried out to find out the impact of teachers' communication skills on the academic achievement of students at the secondary school level. The nature of the study was descriptive, and a Quantitative research design was adopted to investigate the problem. The target population of the study was all the Secondary School Teachers and students of class 10th in Government (boys) Schools in the province of Khyber Pakhtunkhwa (KP), and the accessible population was all the 1315 SSTs and all the 18453 students of class 10th in the Government (boys) Schools in two districts of KP- Mardan and Nowshera. A self-developed closed-end questionnaire was used as an instrument for the collection of data from the respondents, teachers, and students. The average Reliability of the questionnaire was 0.98. The reliability coefficient confirmed that the instrument was highly reliable. The sample size (200 teachers and 400 students) was determined with the help of an online calculator. A simple random sampling technique was used for the selection of respondents from the accessible population. The data was quantified and tested using a regression test. Results of the regression test showed a positive but insignificant impact of teachers' communication skills on the academic achievement of students at the secondary school level. The findings of the study were that teachers use speaking and writing skills better than listening and body language skills, and the impact of teachers' communication skills on the academic achievement of students was positive but low and insignificant.