In the present study, the expression of 14 genes was comparatively evaluated between planktonic and biofilm cells of S. Enteritidis. These genes were selected based on previous knowledge on their putative involvement in stress related mechanisms and other colonization implications. Biofilms were left to be formed on stainless steel coupons incubated under static conditions in brain heart growth medium at either 10 or 20°C for 6 days (144 h). Results revealed significant differential expression for the genes studied between the two growth modes (planktonic, sessile).