Methylpyridinium is an ion with the formula . It is the N-methylated derivative of pyridine. It confers no color to its salts. The ion is classified as a quaternary ammonium ion.
Methylpyridinium is prepared by treating pyridine with dimethylsulfate:
It is found in some coffee products as a result of the thermal decarboxylation of trigonelline.
The chloride salt of N-methylpyridinium behaves as an ionic liquid. Mixtures of that salt and zinc chloride have been characterised over the temperature range .