A multi-tube pyrolysis system for waste plastic contains: a preparation system, a decomposition system, and a filtration system. The preparation system includes a collection module, a selection module, a crushing module, and a plastic extrusion module. The decomposition system includes a reaction furnace, a primary combustion chamber assembly, a secondary combustion chamber assembly, a cooling module, an oil storage tank, and a carbon storage tank. The reaction furnace includes multiple first delivery tubes, and the carbon storage tank has a water filtering module. The filtration system includes a heat exchanger, a rapid cooling device, and a cyclone separation module.