The Tom (, ; ; ) is a river in Russia, a tributary of the Ob in central Siberia. Its watershed lies within the Republic of Khakassia, Kemerovo Oblast, and Tomsk Oblast. It is long, and has a drainage basin of .
The Tom flows from the Abakan Range (a northern continuation of the Altai Mountains) northward through the Kuznetsk Basin. It joins the Ob approximately north of Tomsk.
Cities on the Tom River include Mezhdurechensk, Novokuznetsk, Kemerovo, Yurga, Tomsk, and Seversk.
The Aba people live near the Tom River.
The name of the river may derive either from the Ket word toom ("river") or from the Russian word tyomny ("dark").
The largest tributaries of the Tom are, from source to mouth: