The utility model discloses a unidirectional ball-type support for a bridge and belongs to the technical field of highway bridges. The unidirectional ball-type support comprises an upper support plate, a middle steel plate and a lower support plate which are assembled from top to bottom, a limiting guide groove is formed in the middle of the middle steel plate, a guide block matched with the guide groove is arranged in the same, the guide block and the upper support plate are limited by adopting multiple limiting pins, the upper support plate and the middle steel plate are in planar fit, the middle steel plate and the lower support plate are in spherical fit, and the upper support plate and the lower support plate are connected and limited by limiting mechanisms. The unidirectional ball-type support is a fixed ball-type support capable of realizing vertical load bearing, rotating and safe unlocking of the bridge under action of seismic load, an objective of changing from the fixed support to a movable support is achieved, and seismic displacement of the support is limited by adopting the limiting mechanisms.