Alkylation of aniline with methanol over AlPO4-5, AlPO4-11, CoAPO-5, CoAPO-11, ZAPO-5 and ZAPO-11 in the vapour phase has been studied. The products formed are N-methylaniline (N-MA), N,N-dimethylaniline (NN-DMA) and N-methyltoluidine (N-MT). The product distribution is influenced by temperature, (WHSV)(-1) and ratio of aniline and methanol. Acidity of the catalysts plays an important role in the methylation of aniline. A direct relationship between total acidity and conversion was observed.