The invention relates to a feed distributor of a slurry bed reactor, which comprises a main air inlet pipe and at least two layers of feed distribution pipes, wherein the main air inlet pipe runs through the bottom center of the slurry bed reactor and is arranged vertically upwards; each layer of the at least two layers of the feed distribution pipes comprises at least two round distribution pipes arranged concentrically in the radial direction of the reactor, and radial connection pipes; each layer of the at least two layers of the feed distribution pipes is vertically intersected with and is in gas communication with the main air inlet pipe in the center respectively; the round distribution pipes and the radial connection pipes are provided with open pores at intervals uniformly; the open pores face bottom openings of the reactor; the peripheries of the open pores and the open pores are concentrically provided with surrounding edges; and the open pores formed on each radial connection pipe have a set distance from the main air inlet pipe respectively. By using the feed distributor of the invention, gases can be uniformly sprayed out from each open pore of the feed distributor toprevent refracted flows and avoid catalyst abrasions.