Water cooled turbocharger with heat insulation

A turbocharger (10) includes a turbine housing (31) adapted to be arranged in an engine exhaust passage (3), a bearing housing (11) coupled to the turbine housing, a turbine wheel (33) located inside the turbine housing, a rotary shaft (12) that is connected to the turbine wheel and is rotationally supported by the bearing housing, and a cooling water passage (39) that is provided inside the turbine housing. The cooling water passage is located around the turbine wheel. The turbine housing includes a first connection portion (C1) joined to the bearing housing, a second connection portion (C2) joined to a part of the engine exhaust passage located on a downstream side of the turbine housing, and a heat insulating cavity (41, 42) located between the cooling water passage and at least one of the first connection portion and the second connection portion.