This research project investigated the learning strategies of junior secondary students in Hong Kong ESL classrooms. A total of 132 Form One to Form Three students from 56 schools were studied, observed and interviewed: data were collected accordingly. Students were categorized into "successful" language learners and "unsuccessful" language learners according to their English language academic achievement. Data findings from this research showed that the "successful" language learners employ meta-cognitive strategies more frequently than the "unsuccessful" ones. They tended to plan, evaluate and reflect more on their approach to language learning and ways to improve their English. The two groups did not show a significant difference in group work mode of learning, yet, the "successful" language learners preferred to work on his / her own more. The level of father's education was found to be associated with the type of learning strategies used by students, however, gender did not seem to affect the choice of learning strategies. These findings have important implications for language teachers in helping their students develop effective language learning strategies.