The invention provides a monitoring and alarming method for the abnormal condition of a UPS (Uninterruptible Power Supply). According to the monitoring and alarming method, current monitoring is performed on a line incoming end of the UPS, and working temperature of the UPS is monitored. The monitoring and alarming method specifically comprises the following steps of S1, configuring a current sensing device for respectively monitoring one or more paths of current, inputted into the UPS, of a current input power supply, and configuring a temperature sensing device for monitoring the working temperature of the UPS; S2, processing detection data of the current sensing device and detection data of the temperature sensing device, extracting one or more paths of current effective values I1, I2 until In and a temperature effective value Te outputted by the current input power supply; S3, acquiring a total current value Ii; S4, judging the total current value Ii and the temperature effective value Te, controlling the alarming work and transmitting information to predetermined terminal equipment according to the judgment result. According to the monitoring and alarming method provided by the invention, the line incoming end of the UPS is monitored, multiple guarantee is provided for accurate fault information transmitting, the faults are timely found and removed, and the work reliability of the UPS is facilitated and guaranteed.