The effect of autoclaving on the nutrients' apparent digestibility coefficient (ADC), digestible protein and energy of pea seed meal (P. sativum) fed to Rainbow trout (O. mykiss) was examined. Two samples of the pea meal were autoclaved at 121°C and 1.1 atm for 5 min (5'APM) or 15 min (15'APM), respectively. A third sample, used as control, was not treated (RPM). One reference diet (Basal diet) and 3 experimental diets were elaborated and labelled based on autoclaving time applied to the ingredient (RPM, 5'APM and 15'APM). The four diets were assigned using a completely randomised design, with each treatment having three replicates. 12 tanks were stocked each with 15 trouts with an average weight of 235 ± 10.4 g. Faeces were collected over a 7-day period using a settlement column and pooled within the tank. ADCs were determined using chromium oxide (Cr(2)0(3)) as an inert digestibility indicator. No significant differences (P>0.05) regarding protein ADC were found among all treatments. On the other hand, dry matter, energy and nitrogen free extract (NFE) ADC showed significant differences (p<0.05) among all the different treatments. Results showed that 5'APM improved dry matter, protein, and energy ADC of the dehulled pea seed meal in diets for rainbow trout.