This study was conducted to find out the anthropometric, biosocial and obstetric predictors of birthweight in Kerala. The study sample consisted of 599 consecutive liveborn babies delivered at SAT Hospital, Medical College, Thiruvananthapuram and their mothers in November 2001. Details of maternal history, anthropometry, and biosocial and demographic factors were recorded. Birthweight was primary outcome variable. Multivariate analysis revealed that the biologically acceptable predictors of birthweight of a baby in our population are maternal height (P <0.001), parity (P < 0.001) gestational age (P < 0.001), pregnancy induced hypertension(P=0.05) and history of low birthweight in the previous pregnancy(P=0.05).