The invention discloses a multi-tube pass ethylene pyrolysis furnace. Multi-pass furnace tubes are adopted at a radiation section of the ethylene pyrolysis furnace, the number of the passes of the furnace tubes is from four to ten, the tubes are branch reducing or non-branch reducing tubes, residence time is 0.3 to 1.0 seconds, and the furnace tubes are distributed in the center of a hearth in a single row. High-temperature tube passes and low-temperature tube passes are totally or partially staggered; and the bottoms of all the tube passes are totally or partially connected through S bent pipe and symmetrical bent pipe combination connecting pieces. The invention provides the multi-pass ethylene pyrolysis furnace with a new furnace tube structure, which can improve the heating conditions of the furnace tubes, make the furnace tubes heated uniformly, improve mechanical property of the furnace tubes of the radiation section and one-line rate of a pyrolysis furnace, reduce operation cost and prolong the service life of the furnace tubes, and finally improves economic benefit.