The Rusenski Lom (Bulgarian: Русенски Лом) is a river in northeastern Bulgaria, the last major right tributary of the Danube. It is formed by the rivers Beli Lom and Cherni Lom, the former taking its source south of Razgrad and the latter southeast of Popovo.
The source of the Beli Lom at 43°24′N 26°40′E / 43.400°N 26.667°E / 43.400; 26.667 and 360 m above sea level is provisionally accepted as the point where the Rusenski Lom starts. Before they merge, the two rivers have a length of 130 km for the Cherni Lom and 140 km for the Beli Lom and a drainage basin of 1,549 km² and 1,276 km² respectively. Both rivers primarily run northwestwards, with the Beli Lom going west at Senovo and the Cherni Lom flowing northeast after Shirokovo, as the two rivers get closer to merge north of Ivanovo. The Rusenski Lom empties into the Danube at the city of Rousse, which gives the river its name, with a total length from the source of the Beli Lom being 196.9 km. The coordinates of the mouth are 43°50′N 25°56′E / 43.833°N 25.933°E / 43.833; 25.933, 18 m above sea level.
The Rusenski Lom flows through the Rusenski Lom Nature Park.