There is provided a press-fit lubricant composition comprising an unsaturated compound with an iodine value of 100 or more.

A grease composition includes a urea-based thickener; a synthetic hydrocarbon oil and/or a mineral oil as a base oil, a kinematic viscosity of the base oil at 100 C. being 4 to 40 mm.sup.2/s; and 1 to 10% by mass of a montan wax, 1 to 5% by mass of a molybdenum-based extreme pressure agent, and 1 to 5% by mass of a sulfonate-based compound as additives, and the grease composition has a consistency of 310 to 430. The grease composition is for use in lubrication between a metal member and a metal member and lubrication between a metal member and a resin member.