This paper reports the findings of the study on the relationship between socio-economic status (SES) variables and students' achievement in learning ESL (AESL) in a few selected secondary schools of India. Through this study an attempt has been made to predict which variable of SES affect students' AESL. A questionnaire survey has been used to collect information about SES variables (father and mother education, father and mother occupation and family income) of the students. The students' AESL in form of grades is taken from the schools. Data analyses have been done using SPSS by descriptive and inferential statistics. Analysis of variance (ANOVA) and multiple regression analysis findings indicated that students' AESL is dependent on five SES variables. Multiple regressions indicated that fathers' education, mothers' occupation and income are significant predictors. This reflects that there is a need to look into these factors in addition to school learning factors affecting students' learning English as a second language (ESL).