The invention discloses an oil sludge cleaning and processing system for an oil tank. The oil sludge cleaning and processing system comprises a cleaning system, an oil sludge processing system and an integrated control system, wherein the cleaning system comprises a cleaning robot, an electric hydraulic pump, a water pump, an inert gas storage tank and a screw pump; the cleaning robot comprises a machine body, a traveling unit, a cleaning unit, a robot cleaning control unit, a sensing and communication unit and a robot power supply unit; the oil sludge processing system comprises an oil sludge processing device, an oil sludge processing control system and an oil sludge processing power supply device; the oil sludge processing device comprises a stirring machine, an ultrasonic emulsion breaking device, a centrifuge and an ultrafiltration system, as well as an oil sludge storage pool, a sludge pool, a centrifugal liquid storage tank, a concentration tank and a filtrate pool; a funnel is arranged on the stirring machine; and the integrated control system comprises an integrated control computer and a communication circuit module. The oil sludge cleaning and processing system disclosed by the invention has the advantages of reasonable design and high degree of intelligentization, and can realize comprehensive cleaning of the oil tank, good safety, fast oil sludge processing speed and resource utilization of oil sludge, and further reduce environmental pollution and waste of resources.