This study aimed to investigate the effects of seasonal differences and crating densities on the behavior, surface temperature, and respiration rate of broilers during transportation. A total of 600 broilers aged 35 days were divided into 10 treatment groups based on five crating densities (10.3, 11.5, 12.8, 14.1, 15.4 birds/m 2 ) with two seasons (i.e. summer and winter) to give six replicates. Broilers were allocated to the crates (1.00 m × 0.78 m × 0.26 m) in a randomized design. The transportation distance was 20 km for 40 minutes (average 30−50 km/h) during the early morning. The results revealed that standing behavior of broilers during transportation was shown more frequently (P<0.05) in winter. Moreover, sitting behavior was significantly shown (P<0.05) more at densities of 14.1 birds/m 2 and 15.4 birds/m 2 compared to other treatments. Standing behavior was significantly shown more (P<0.05) in winter and lower crating density. Changes in broilers surface temperature after transportation were higher (P<0.05) in summer. However, surface temperature after transportation was not affected (P>0.05) by crating density, and interaction between seasonal differences and crating density. Respiration rate was higher (P<0.05) in summer. But there were no effects (P>0.05) on respiration rate based on crating density, and interaction between seasonal differences and crating density. Based on the results of the present study, broilers transportation is recommended in winter rather than summer to minimize the climatic stress, but further research is required to identify proper crating densities to improve the broilers welfare during transportation.