Nevada Mining Townsite Conveyance Act - Sets forth procedures for the conveyance of certain mining townsites. Defines a mining townsite as real property in the counties of Esmeralda and Nye, Nevada, that is owned by the Federal Government but upon which improvements have been constructed because of a mining operation on or near the property, if such improvements were undertaken based on the belief that: (1) the property had been or would be acquired by the entity operating the mine; or (2) the person who made the improvement had a valid claim for acquiring the property.

Directs the Secretary of the Interior, acting through the Bureau of Land Management, to convey, without consideration, all right, title, and interest of the United States in and to certain mining townsites to the county in which each site is located. Directs, if a valid interest is proven in a site under Nevada law, the county receiving such site to reconvey the property to the person or persons with such interest. Requires, for a claim to be valid, the claimant to have occupied the relevant mining townsite for at least 15 years immediately before the enactment of this Act.

Provides for the protection of historic and cultural resources on conveyed townsites. Subjects conveyances under this Act to valid existing rights.