Genetic parameters of test day (from birth to sixth month) body weight and body size parameters of Saanen kids were estimated by random regression with third order Legendre polynomial. The analyses were applied to 2673 test day records of 382 Saanen kids (Twin = 328; Single = 54; Female = 204; Male = 178) in a private dairy goat farm in Samsun, at the black Sea region of Turkey. Permanent environmental variances were static for height at sacrum, height at withers and chest depth, increased for body weight and body length on time. Heritability values ranged from 0.2679 to 0.6135 for body weight and Height at withers. Genetic correlations changed between 0.725 and 0.979 in all traits. The positive high genetic correlations among traits suggested that selection for any one of these traits would result in considerable positive change in other traits.