Provided is a valve gear in which corrosion due to a potential difference does not occur and which can reduce the corrosion occurrence even when loads due to microvibrations are given. The valve gear according to the present invention comprises a valve stem 6 and a valve bush 7 that slidably supports the valve stem 6. The valve stem 6 is formed from a forged part made of a Ni-based superalloy and the valve bush 7 is formed from a cast part made of a Ni-based superalloy. The preferable surface roughness of a sliding surface of the valve stem 6 in contact with the valve bush 7 and the preferable surface roughness of a sliding surface of the valve bush 7 in contact with the valve stem 6 is 100 µm or less in units of Rz.