The invention discloses an oil tank cleaning robot. The robot comprises a robot body, a walking unit, a cleaning unit, a control unit, a sensing communication unit and a power supply unit, wherein the robot body comprises a base plate, a lower casing and an upper casing, the walking unit comprises three driving wheels and three driving wheel hydraulic motors, the cleaning unit comprises a cleaning device and a self-excitation pulse device, the cleaning device comprises three cleaning disk brushes and three cleaning disk brush hydraulic motors, the self-excitation pulse device comprises a pulse device hydraulic motor, a retractable beam assembly and a self-excitation oscillating pulse nozzle, the control unit is composed of a remote control portion and a robot body control portion, and the sensing communication unit comprises a pressure sensor, a temperature sensor, an infrared sensor, an ultrasonic sensor, a horizontal attitude sensor, a turbidity sensor, a camera and an oil-gas concentration monitor. The robot is novel in design, high in intelligent degree, high in working reliability, good in safety performance, energy-saving, environment-friendly, high in practicability, high in popularization and application value and capable of achieving omni-directional cleaning.