The main purpose of this study was to determine the effects of Peer-Led Team Learning (PLTL) strategy on the achievement and engagement level students in Chemistry. It was conducted at Casimiro A. Ynares Sr. Memorial National High School, Taytay, Rizal during the third quarter period of the school year 2018-2019. The participants of this study were chosen using purposive sampling. The sample students belong to one intact section of Grade 9 composed of 36 students. This study utilized a one-group pre-experimental research design. The results revealed that there is a significant difference in the chemistry achievement and engagement level of the students before and after their exposure to Peer-Led Team Learning. Significant difference was found in all the CIP engagement factors which are; cooperation, interest and participation after the students were exposed to PLTL. In overall there is a significant difference in the engagement mean of students before and after the implementation of PLTL. It was concluded that the use of Peer-Led Team Learning had positive effects to the learning achievement in chemistry and engagement of students. The workshop participants revealed they are felt comfortable learning under the peer leaders because they approachable and they were able to execute the lessons properly and clearly. The students also enjoyed sharing ideas and working with each other that triggered cooperation among them.