Abstract: As one of the top ten natural disasters, landslides have great impacts on the environment and on societies, and often cause vast economic losses and casualties. Many methods have been developed for the prediction or forecast of landslides; however, results are not very satisfactory. Two kinds of triggering factors are currently considered in prediction or forecast of landslides: natural and man-made. Under given geological and geomorphic conditions, rainfall becomes a key natural factor. Based on philosophical thoughts on the prediction or forecast of landslides, the authors suggest that the method of weather-slope forecast, in which probability of occurrence of landslides was calculated based on the forecast of rainfall, be enhanced,. As expected, by integrating the weather slope forecast with the monitoring of landslides, the resulting method could improve the accuracy of prediction or forecast of landslides.