The present study investigated the correlation of critical thinking skills (CTS) and academic achievement of intermediate students in the province of Punjab, Pakistan. The study was quantitative. The population of the study comprised all the students enrolled for intermediate in the province of the Punjab. Multistage sampling technique was used to select a sample size of 300. CTS test scores were obtained from a self-developed multiple-choice test having dimensions of analysis, evaluation, and logic.  Scores of the academic achievement was obtained from the selected sample. It was found that the majority of students at intermediate level performed low on analysis, evaluation, and logic dimensions of the critical-thinking skills. The study also revealed that there was a significant positive relationship between CTS and academic achievement of  students at the intermediate level. The study recommends introducing teacher guides for teaching CTS at the intermediate level. The study also recommends introduction of continuous assessment procedures for the development of the CTS in students at the intermediate level.