The invention relates to a method and a system for generating acetylene and synthesis gas by partial oxidation of methane containing gaseous hydrocarbon. The system comprises a combustion chamber, a heat and solid product recovery device and a gaseous product collection device in sequential connection. A gaseous hydrocarbon inlet and an oxygen inlet are respectively connected with a burner nozzle at the top end of the combustion chamber; a gaseous hydrocarbon flow passage and an oxygen flow passage in the burner nozzle form acute angles with the perpendicular line respectively and are internally provided with swirl plates respectively, and gaseous hydrocarbon and oxygen are well mixed while entering the combustion chamber in a swirling manner. The method and the system for generating acetylene and synthesis gas by partial oxidation of methane containing gaseous hydrocarbon have the advantages that high-temperature products can be cooled to realize reaction termination after being discharged from the combustion chamber, excessive heat is recovered for use, and accordingly heat utilization rate is effectively increased; since the gaseous hydrocarbon and the oxygen are heated and sprayed into the combustion chamber through the burner nozzle and are reacted during mixing, the problem of equipment burnout due to early firing is avoided, and prevention of early firing of a mixing area, high heat recovery and comprehensive utilization rate and suitableness for large-scale industrial production are realized.