This study aimed to verify the influence of the transport in open or closed compartments (0h), followed by two resting periods (1 and 3h) for the slaughter process on the levels of cortisol as a indicative of stress level. At the slaughterhouse, blood samples were taken from 86 lambs after the transport and before slaughter for plasma cortisol analysis. The method of transport influenced in the cortisol concentration (0h; P<0.01). The animals transported in the closed compartment had a lower level (28.97ngml −1 ) than the animals transported in the open compartment (35.49ngml −1 ). After the resting period in the slaughterhouse, there was a decline in the plasmatic cortisol concentration, with the animals subjected to 3h of rest presenting the lower average cortisol value (24.14ngml −1 ; P<0.05) than animals subjected to 1h of rest (29.95ngml −1 ). It can be inferred that the lambs that remained 3h in standby before slaughter had more time to recover from the stress of the transportation than those that waited just 1h. Visual access to the external environment during the transport of the lambs is a stressful factor changing the level of plasmatic cortisol, and the resting period before slaughter was effective in lowering stress, reducing the plasmatic cortisol in the lambs.