The invention discloses a method for monitoring farmland drought, which comprises obtaining soil or leaf water content of an observing point which is arranged on monitoring ground surface, building a functional relation between soil or leaf water content of the observing point and a corresponding index of characterized farmland drought condition, taking remote sensing data into the functional relation, and obtaining the soil or leaf water content of the monitoring ground surface, wherein the corresponding index of characterized ground surface drought condition is defined according to following methods: Firstly, the farmland ground surface whose vegetation coverage< =15% adopts a vertical drought index, secondly, the farmland ground surface whose vegetation coverage>15% and <= 65% adopts a vegetation conditions albedo drought index, and thirdly, the farmland ground surface whose vegetation coverage>65% to 100% adopts at least one of three following indexes: a short wave infrared vertical water loss index, a vegetation water content index, and a vegetation water deficit index. The ground surface drought monitoring method of the invention is applied for drought testing farmland ground surface with different vegetation coverage degrees.