Language learning strategies Academic self-concept English language learning Academic success PredictionThis study aims to identify the factors influential in academic achievement in learning English. The study was conducted with the participation of 522 students who were the ninth, tenth and eleventh graders in an Anatolian High school located in Ankara city centre. The research data were collected with the Turkish version of personal and academic self-concept inventory (PASCI-Fleming & Whalen, 1984) and of strategy inventory for language learning (SILL-Oxford, 1990) (Cesur & Fer, 2007). The data were then analysed through bivariate correlation coefficient and multiple linear regression analysis. As a result, significant correlations were found between academic achievement in English and all sub-factors of learning strategies and of academic self-concept (p<.01). It was found that all the variables analysed (gender as male students, grade 11 as class variable, language learning strategies, academic self) predicted 42% of the variance in academic achievement in English. In the study, it was found that cognitive, compensatory and metacognitive strategies which are language learning strategies positively predicted English academic achievement while affective strategies predicted negatively. In the academic self-dimension of the study, it was found that academic ability and family acceptance positively predicted academic success in English while physical appearance and social anxiety predicted negatively.