A Descriptive-correlational study was sought to investigate the influence of metacognition on the academic achievement and learning style of undergraduate students. Using the survey method, data was collected from a sample of 150 undergraduate students selected through a stratified random sampling technique which includes 50 students each from the three schools namely School of Humanities and Social sciences (HSS), School of Engineering (SOE), and School of Sciences (SOS) of Tezpur University. The tools used are five-point Likert-type Metacognitive skills scale and five-point Likert-type Learning Style Inventory. Academic Achievement of the students was measured based on the semester grade point average SGPA obtained in the semester examination. The data were analyzed using percentage, simple regression, multiple regression and one-way ANOVA. The result showed that only 34-36% of the undergraduate students have above-average metacognitive skills. The undergraduate students have equal preferences in all the five learning styles rather than focusing on one learning style. There is a significant difference between metacognition levels and academic achievement of the undergraduate students of SOS, HSS and SOE. The metacognitive skill explicates only 43% variability of academic achievement of the undergraduate students which implies that the undergraduate student's metacognitive skills influence and determines their academic achievement to some extent. However, the undergraduate student's learning style doesn't account for variation in metacognitive skills. Thus, it is suggested that metacognitive skills should be integrated into curricular components and learning strategy which will help the students to monitor and regulate their own learning to meet the challenges of academic society.