The invention relates to a material feeding container for two-cylinder thick matter pumps. The material feeding container (24) has a material supply opening (30) oriented upward, two feed cylinder openings (34) arranged in the front wall (36) of the container and a transfer tube having the shape of an S-tube (42), which is arranged inside the container with its input end (48) swiveling in an alternating manner in front of the feed cylinder openings (34) and mounted on the output side in a feed-through opening (46) of the rear wall (38) of the container that is arranged above the feed cylinder openings. A pressure pipe (40) is connected to the outer side of the rear wall (38) of the container, the output side (44) of the S-pipe (42) leading into said pressure pipe. According to the invention, a maintenance opening (56) is arranged on the rear wall (38), which is formed by an opening defined by a peripheral edge (58). The maintenance opening (56) can be closed with a cover plate (60), which has a top cover plate part (64) that is oriented perpendicular to the swiveling axis (50) of the S-pipe (42) and includes the feed-through opening (46) for the S-pipe (42) and a bottom cover plate part (68) that forms an inclined bottom part and that is connected to said top part substantially parallel to an S-pipe segment (66) extending obliquely downward.