This study aims to determine the relationship between body weight in the Philippine deer and its external body measurements such as heart girth, midriff girth, flank girth, body length and body width, and to construct prediction equations for body weight determination based on the said parameters. A total of 80 apparently healthy Philippine deers consisting of 28 males and 52 females with ages ranging from 8-48 mos were used in the study. Regression analysis revealed that a linear relationship exists between body weight and external body measurements. Midriff girth was found to be the best single predictor of weight, regardless of sex and age. Where multiple parameters are used for predicting weight, midriff girth and width at shoulder were found to have the highest correlation to weight, regardless of sex and age. A comparison of the actual weights and the estimated weights derived from the regression formulae disclosed no significant differences (P>0.05). Hence, these formulae could be used to estimate body weight in the absence of a suitable weighing scale.