A system, apparatus and method for detecting a porous object are provided. The system includes a light emitting module, a detecting module and an analyzing module. The light emitting module emits light onto an object to be measured such that the light passes through a plurality of holes of the object. The detecting module has a porous plate having a plurality of non-circular holes and a plurality of photosensitive units respectively corresponding to the non-circular holes. Each of the non-circular holes corresponds to at most one of the holes at one time point. The light passes through the plurality of non-circular holes corresponding to the plurality of holes. The photosensitive units respectively sense luminous flux of the light passing through the plurality of non-circular holes to produce a luminous flux signal. The analyzing module analyzes a status of the plurality of holes corresponding to the plurality of non-circular holes.