Disclosed are an instant combustion-type particulate matter trap and a trapping method therefor. The instant combustion-type particulate matter trap comprises a particulate matter trap body (1) and an oxygen pump (2), the particulate matter trap body comprising an inflow port (1-1), an outflow port (1-2) and a filtration portion (1-3), the oxygen pump (2) being arranged at the inflow port (1-1) side of the particulate matter trap body (1). The particulate matter trapping method is: the oxygen pump (2) continually pumps oxygen into the particulate matter trap body (1), so that particulate matter within the particulate matter trap body (1) is instantly combusted. The trap enables combustible particulate matter within the particulate matter trap body to be instantly and fully combusted by an engine during operation, so that the particulate matter trap body is not blocked by particulate matter, extending the activation time or even obviating the need for activation. The amount of variation in the engine exhaust gas back pressure is reduced, and the operating conditions of the engine are stable. In terms of economics, costs are saved, diesel-injection combustion is essentially eliminated, and the costs of the oxygen pump within a lifecycle are far lower than diesel costs. In addition, performance is stable and reliable.