The invention discloses a super-power-density diesel engine with sequential intervention type composite combustion systems. The super-power-density diesel engine with the sequential intervention typecomposite combustion systems comprises a common rail pipe, a high-pressure oil pipe, a cylinder cover, a main combustion chamber oil nozzle, an exhaust pipe, an air inlet pipe, an intercooler, a high-pressure-stage turbine bypass valve, a high-pressure-stage turbine, a high-pressure-stage gas compressor bypass valve, a high-pressure-stage gas compressor, a low-pressure-stage turbine, a low-pressure-stage gas compressor, a cylinder body, a low-pressure oil supply pump, an oil tank, a piston, a main combustion chamber, a hydraulic valve, a filter, an auxiliary combustion chamber, an auxiliary combustion chamber oil nozzle, a high-pressure oil pipe, a high-pressure oil supply pump and a rail pressure valve, and is characterized in that the main combustion chamber (18) communicates with the auxiliary combustion chamber (21) through the hydraulic valve (19), the main combustion chamber (18), the high-pressure-stage turbine (9) and a high-pressure common rail system work cooperatively, an ECU issues an instruction to open the hydraulic valve (19), the auxiliary combustion chamber (21) and a secondary supercharging system intervene, the main combustion chamber (18), the auxiliary combustion chamber (21), the high-pressure-stage turbine (9), the low-pressure-stage turbine (12) and the high-pressure common rail system cooperatively work, and a sensor is arranged on the hydraulic valve (19) and is regulated and controlled through the ECU.