2,2,6,6-Tetramethylpiperidine, abbreviated TMP, HTMP, or TMPH, is an organic compound of the amine class.

In appearance, it is a colorless liquid and has a "fishy", amine-like odor.

Although TMP finds limited use per se, its derivatives are a mainstay of hindered amine light stabilizers.

TMP is the starting material for an even stronger base, lithium tetramethylpiperidide and the radical species TEMPO.

One method[3] starts with a conjugate addition reaction of ammonia to phorone.