In animal production, body weight is an important parameter for management, health and marketing decisions. This study is undertaken to determine the relationships between body weight and linear body measurements of guinea pigs. 120 guinea pigs (60 males and 60 females) were used. Body weight (BW), head-body length (HBL), chest circumference (CC), head circumference (HC), neck circumference (NC), left hind foot length (FL), and left ear length (EL) were the measured traits. The collected data were evaluated using multiple regression analysis. The obtained models of regression are : BW=-397.374 + 10.817HBL + 16.440CC + 12.433NC-19.039EL-12.011FL + 12.458HC ; BW =-560.601 + 4.531HBL + 21.649CC + 6.556NC-6.632EL-2.086FL + 34.370HC ; BW =-477.178 + 7.941HBL + 17.672CC + 8.758NC-10.383EL-1.951FL + 22.884HC, respectively for males, females and both sexes. In the regression model obtained for both sexes, the coefficients of HBL, CC and HC were significant (p < 0.01). The HC and CC coefficients for males and the CC and HC coefficients for females were also significant (p < 0.01). It was concluded that BW of guinea pigs was significantly influenced by CC, HBL, HC using multiple linear regression.