Abstract: The present disclosure provides a method and system for calculating water-land-forage-livestock balance in a family pasture by taking forage quality into account. The method takes a family pasture as a calculation unit and starts from a water circulation process, various types of groundwater recharges of the family pasture are calculated, and an available groundwater quantity is calculated by using an exploitable coefficient method, and undergoes water-land balance calculation with an irrigation water demand and a drinking water demand of people and livestock; and total digestible nutrients of various types of forage are used to convert each type of forage into standard hay for forage-livestock balance calculation, so as to determine a maximum supportable planting area of irrigated artificial grasslands and a maximum supportable quantity of livestock raised in the family pasture.