Abstract The impact of smoking on the lipid fraction of seabob shrimp ( Xiphopenaeus kroyeri, Heller, 1862) was evaluated by the formation of cholesterol oxides and changes in fatty acid composition and in nutritional quality. In addition, cholesterol and chloride contents, pH, and proximate composition were determined. Smoking reduced lipid and protein contents and increased ash and chloride concentrations, while the pH value remained constant. Despite the loss of 18:2n6 (53%), 20:4n6 (50%), 22:6n3 (49%), 20:5n3 (47%) and 18:1n9 (44%), the n6/n3 ratio did not change significantly. The index of atherogenic (0.82) and of thrombogenic (0.62) were low after smoking. Smoking also caused losses of cholesterol (2 7 %) and 7β-hydroxycholesterol (50%), while 7-ketocholesterol and 7α-hydroxycholesterol contents remained constant.