Greaseproof papers of different air permeance (AP) were coated with chitosan, both on a bench scale and a pilot scale to study the conditions to obtain a packaging material with low oxygen permeability (OP) and high grease resistance. The results showed that excellent OP, in the same range as for PETP poly(polyethylene terphatalate), was obtained at coat weights exceeding 5 g/m². Also, at this coat weight excellent grease resistance were obtained. On the other hand, the coated papers did not yield any barrier against water. However, that coat weight could only be obtained on papers coated on a bench scale. On a pilot scale the maximum coat weight was 0.2 g/m². That low coat weight was due to the low solids of the coating solution used which was only 1.0%. The coating on a pilot scale was performed using metered size press technique. To increase the coat weight the solids of the solution must be increased to approximately 20%. This presupposes a considerably lower molecular mass of the chitosan than that of the product used in this study. A coating technique which allows higher coat weights might also be necessary