The river flows through Tymovsky and Nogliki Districts of Sakhalin Oblast.

It begins on the southern slopes of Mount Lopatin in the East Sakhalin Mountains, flows through swampy lowlands in the Tym-Poronaiskaya Valley, and finally flows into Nyisky Bay in the Sea of Okhotsk.

The Tym freezes between November and early December, and the spring break occurs between the end of April and May.

[3][4] Some agriculture is carried out in the Tym valley, producing potatoes and vegetables, as well as raising cattle for meat and dairy products.

Although the growing season averages less than 100 days, Soviet scientists optimistically called the river valley "the granary of Sakhalin".