The utility model discloses a chip blocking detector of a chain plate-type chip cleaner; in order to overcome the problem of the chip blocking detection of the chain plate-type chip cleaner in the existing numerical control machine tool. The chip blocking detector of the chain plate-type chip cleaner consists of an induction part and an alarm part; the induction part comprises an inlet light curtain sensor (1) and an outlet light curtain sensor (3); the alarm part consists of an alarm box (10) and an alarm circuit; the alarm circuit is arranged in the alarm box (10); the alarm part is arranged at the top part of the chain plate-type chip cleaner (5); the inlet light curtain sensor (1) is arranged at the inlet (X) of the chain plate-type chip cleaner; the outlet light curtain sensor (3) is arranged at the outlet (Z) of the chain plate-type chip cleaner; the signal output line of the inlet light curtain sensor (1) is connected with one of poles of inlet alarm equipment (8) in the alarm part; the signal output line of the outlet light curtain sensor (3) is connected with one of terminals of a coil of a time-delay relay (9) in the alarm part.