The body surface area (BSA) of an organism is one of the important parameters for evaluating physiological functions. In drug development, normalization by BSA is an appropriate method for extrapolating doses between species. The BSA of animals has generally been estimated by multiplying the k value by 2/3 of the power of the body weight (BW) (Meeh's formula). In mathematics, if it is assumed that the density and body shape of the animals are essentially constant, the BSA is proportional to BW2/3. In this study, we measured the BSA and volume (V) of 72 laboratory rabbits (48 males and 24 females of New Zealand White rabbits [NZW]), using a computed tomography scanner. After BSA and V determination, the k value, density, and sphericity were calculated. We analyzed variations in the k value, density, and body shape of laboratory rabbits. The mean k value of the 72 NZW was 11.0. We advocate using Meeh's formula, as follows, for estimating BSA of laboratory rabbits (NZW): 100 × BSA [m2] = 11.0 × BW [kg]2/3.