1) The study examined the association between metacognitive ability and academic achievement in science among 9th grade students, and the differences in metacognitive ability based on gender, location, medium of instruction, and school management type. 2) There was a positive and significant correlation found between metacognitive ability and academic achievement in science. Girls and rural students had significantly higher metacognitive ability scores than boys and urban students respectively. 3) No significant differences were found in metacognitive ability based on medium of instruction or school management type.