Routine large-scale assessment of the awareness of iron-deficiency anaemia (IDA), a rampant public health challenge in India, is lacking. We conducted a study, among adolescent girls attending government schools in Srikakulam district, South India, to ascertain the awareness of IDA and identify key socio-economic correlates of IDA awareness. We collected biometric, demographic and survey data, from 148 randomly selected schoolgirls, from one urban and one rural school, and conducted t-tests and discriminant function analyses. Participants (mean age of 13.48 (1.08) years; mean body mass index (BMI) of 17.53 (0.21) kg/m2) scored a mean of 24.63 (4.21) out of a possible 41 (rural–urban (95%CI) = (−2.9, −0.2)). Discriminant function loadings revealed age (0.79), mother’s education (0.43) and occupation (0.59), father’s occupation (0.59), number of female siblings (0.36) and BMI (0.78) to be key determinants of IDA awareness. The low scores on IDA awareness and the high proportion of underweight participants highlight the need for targeted health education and nutrition interventions.