An experiment on New Zealand White (NZW) and Californian (CAL) rabbits was carried out to evaluate genetically post wearing coat traits of these two breeds raised under hot conditions. Data on 24680 and 10549 fibers collected from 1234 NZW and 520 CAL weaned rabbits were used, respectively. At 8 and 12 weeks of age, post-weaning coat traits included average hair length in cm (HL), hair diameter (pm) in down hair (HOD) and guard hair (HOG), medulla diameter (pm) in down hair (MOD) and guard hair (MDG), and medullation percent in down hair (PMD) and guard hair (PMG). Variance components and sire heritabilities were estimated for these trals using Restricted Maximum Likelihood (REML procedure. Transmitting abilities (TA) for these traits were estimated using a single-trait Animal Model (AM). Most postweaning coat traits in CAL were slightly higher than those in NZW. The estimates at 8 and 12 weeks, respectively were 2.4 and 3.0 cm in NZW vs 2.4 and 3.1 cm in CAL for HL, 12,2 and 18.8 pm in NZVV vs 12.2 and 18.9 pm in CAL for HDD, 62.1 and 89.1 pm in 117W vs 62.3 and 88.9 pm in CAL for HOG, 10.2 and 16.4 pm in NZW vs 10.2 and 16.4 pm in CAL for MOD, 51.4 and 78,1 pm in NZVV vs 51.5 and 77.8 pm in CAL for MDG, 82.2 and 87.1 % in NIZW vs 83.5 and 86.3 % in CAL for PMD, and 82.2 and