A copper alloy sheet with a Sn coating layer comprises a base material made of Cu—Ni—Si system copper alloy. Formed on the base material is a Ni coating layer having an average thickness of 0.1 to 0.8 μm. Formed on the Ni coating layer is a Cu—Sn alloy coating layer having an average thickness of 0.4 to 1.0 μm. Formed on the Cu—Sn alloy coating layer is an Sn coating layer having average thickness of 0.1 to 0.8 μm. A material surface is subject to reflow treatment and has arithmetic mean roughness Ra of 0.03 μm or more and less than 0.15 μm in both a direction parallel to the rolling direction and a direction perpendicular to the rolling direction. An exposure rate of the Cu—Sn alloy coating layer to the material surface is 10 to 50%. A fitting type connection terminal requiring low insertion force can be obtained at a low cost.