The invention discloses a coal gasifier slag clock and a manufacturing technology thereof. The coal gasifier slag clock includes a shell, a slag water inlet and a slag water outlet, wherein the shellincludes an elliptical head, a cylinder body and an edge-fold conical head, an upper valve seat is installed on the elliptical head and the slag water inlet, a lower valve seat is installed on the slag water outlet, a guiding device is arranged in the cylinder body, the guiding device includes an upper valve guiding sleeve, a lower valve guiding sleeve, an upper valve rod, a lower valve rod, an upper valve element and a lower valve element, an upper shaft sleeve, an upper supporting ring, a lower shaft sleeve and a lower supporting ring are installed on the cylinder body, an upper driving mechanism used for driving the upper valve rod to slide up and down in a reciprocating mode is installed between the upper shaft sleeve and the upper supporting ring, and a lower driving mechanism used for driving the lower valve rod to slide up and down in a reciprocating mode is installed between the lower shaft sleeve and the lower supporting ring. According to the coal gasifier slag lock, the structure design is reasonable and compact, the manufacturing technology is advanced in technique, manufacturing precision is high, manufactured equipment has the good sealing property, operation is stable in the use process, and the occurrence rate of a breakdown is low.