The invention provides a hydraulic oil cylinder used for a material pumping system. The hydraulic oil cylinder comprises a cylinder barrel, a piston and a piston rod installed in the cylinder barrel; two ends of the cylinder barrel are sealed by a first end cover and a second end cover; one end of the piston rod is arranged on the piston while the other end of the piston rod passes through the first end cover; the inner part of the cylinder barrel is divided into a first cavity and a second cavity by the piston; the invention also comprises a limit piston and a limit piston fixing rod, wherein one end of the piston rod is provided with a blind hole in which the limit piston fixing rod can be inserted; the limit piston can reciprocate on the limit piston fixing rod. The invention also provides a hydraulic oil circuit, a material pumping system and an engineering machinery. According to the technical scheme of the invention, the length of the hydraulic oil cylinder is effectively shortened, the installation space of the pumping system is reduced, the manufacture of the hydraulic oil cylinder and connection of oil pipes are facilitated, the concrete pistons are more convenient and faster to clean and replace, and the continuity of the cement pumping work and the production efficiency are enhanced remarkably.