The invention relates to a load fault diagnosis detection method and a device thereof. Rise phase current waveform sampling is driven through a load, comparison with a preset threshold is carried out, logic overturn of a diagnosis signal which exceeds the threshold occurs, a time of a logic overturn moment of the diagnosis signal is detected, the time and a preset benchmark value are contrasted and analyzed, hereby whether the load has short circuit, circuit break and load over-limit faults is determined, and simultaneously, whether the short circuit fault is short circuit to ground or short circuit to a power supply can be determined; through measuring time of drive starting moment and ending moment of diagnosis signal overturn, comparison with a driving signal is carried out, and hereby whether pulse width output of the driving signal has abnormity or not is determined. According to the method, only a diagnosis circuit is added based on a load performer driving circuit, additional cost is low, protection and control reliability in a load performer driving process can be raised substantially, and a foundation for load driving analysis and fault diagnosis is established.