The invention relates to an online quality monitoring device and method for freeze-dried powder injections. The online quality monitoring device is used for inspecting visible foreign matter in the freeze-dried powder injections and is arranged on the portion, where the freeze-dried powder injections are not filled with medicine liquor yet, and the portion, where the freeze-dried powder injections are filled with medicine liquor already, of a linkage production line. The device comprises a penicillin bottle conveying belt, a liquor filling device, first cameras, second cameras, backlight sources, a computer and an eliminating mechanism. The first cameras are used for shooting images of penicillin bottles, the second cameras are used for shooting images of the penicillin bottles filled with the medicine liquor, the backlight sources are used for providing light sources for shooting of the penicillin bottles, and the computer acquires and analyzes camera image data and feeding back eliminating signals for the penicillin bottles with the visible foreign matter. The invention further relates to the method for inspecting the visible foreign matter of the freeze-dried powder injections by means of the online quality monitoring device. The device and method can be used for quite effectively performing quality monitoring on visible foreign matter inspection items of the freeze-dried powder injections online in advance in a full sample mode.