A material delivery device for a chemical reactor comprises : a funnel-shaped main body (1); an unloading pipe (2) fixedly connected to a port at a bottom portion of the funnel-shaped main body (1) and connected to a material-feeding pipe of a reactor (200); a pneumatic motor (4) fixedly provided at the funnel-shaped main body (1) or the unloading pipe (2); a rotor (5) provided inside the unloading pipe (2) and driven by the pneumatic motor (4), wherein the unloading pipe (2) has a rectangular shape when viewed in a cross section and fits with the rotor (5); and an unclogging mechanism provided inside the funnel-shaped main body (1) and driven by the pneumatic motor (4). The pneumatic motor (4) drives the rotor (5) to rotate, such that a material is discharged from the unloading pipe (2) while the unclogging mechanism simultaneously and repeatedly moves up and down to unclog the material inside the funnel-shaped main body (1).