The invention provides a method of controlling watering by monitoring soil moisture, including the steps of: determining a control moisture and a measuring frequency measuring a soil moisture according to the measuring frequency by a moisture sensor implementing a watering process when the ratio of the soil moisture to the control moisture is lower than a first control value implementing a waiting process after the watering process measuring the soil moisture using the moisture sensor after finishing the waiting process and implementing the step of measuring the soil moisture according to the measuring frequency by the moisture sensor when the ratio of the soil moisture to the control moisture is higher than a second control value, and implementing the watering process and the step of the waiting process when the ratio of the soil moisture to the control moisture is lower than the second control value.
