A failure alarm device includes: an operation instruction capturing unit; an operation status signal capturing unit; and a timing and alarming unit for starting timing when the operation instruction capturing unit captures a start-operation instruction and the operation status signal capturing unit captures an operation status signal indicative of that the CMP apparatus is in the preset operation status, and for alarming if a duration of the operation status signal indicative times out. During operation of the CMP apparatus, when there occurs an unexpected failure in a computer or control software or the CMP apparatus is powered off, an alarm can be initiated in a timely way so as to inform an apparatus engineer to obviate the failure, and wafer rejects in the CMP apparatus can be avoided. A failure alarm method is also provided.