The present disclosure discloses a map data processing method, a device, a storage medium and a program product, and relates to intelligent transportation, automatic driving, electronic map and other fields in computer technology. A specific solution is: determining, according to coordinates of vertexes of a tile included in panoramic map data, coordinates of mapping points of the tile on a plane where a viewport is located; determining a bounding box of the mapping points according to the coordinates of the mapping points; according to whether there is an overlapping area between the bounding box of the mapping points and a visible range corresponding to the viewport, determining whether the tile falls within the visible range, thus determining the indexes of all the tiles falling within the visible range. In this way, the indexes of the tiles falling within the visible range corresponding to the current viewport can be determined accurately.