The utility model discloses a railway piggyback transport car and tray thereof, this tray include the main part, still be provided with the container lock in the main part, the container tool to lock body includes: the mount pad, install in the main part, the spring bolt, set up in the mount pad, the spring bolt can lock with the cooperation of container corner fittings, and the spring bolt with mount pad swing joint, with accomodate in the mount pad is inside or be located the main part below, use the utility model provides a directly hoist and mount transportation of container because of being provided with the container lock on the tray, so it is spacing to utilize the container lock directly to carry on the container, is realized to the piggyback transport car of tray under the function prerequisite that satisfies normal piggyback transport, enlarged the transportation scope of railway piggyback transport car greatly, has increased the flexibility that the piggyback transport car used.