This research was aimed to prevent impairing the performance of the nutrient solution recycling system. Many researchers thought that UV performance was important to the whole process. However, this answer was right or wrong. Actually, in field, the filtration process also was important process. The backwashing process, to adequate clean filtration process during disinfection process, results in the deterioration of the state of the filter bed. In case of inefficient backwashing, filter tend to accumulate aggregates of dirt, media and coagulant known as mudballs. Also the other aim is result and analysis on the backwash cycle and impact of various factors on backwash effectiveness and their implications for the operation of real filter in horticultural greenhouse. The experiment was carried out in a Venlo type multi-greenhouse (experimental area; 16m by 4 rooms as 12.5m for each room) located in resting horticulture field in Gangneung KIST. For the considered during Fall and Winter Season. Spontaneously, these parameters (pH, EC, TDS, TS, Turbidity, DO, Hardness, Alakalinity), was measured under rapid filter process and backwashing process. At the field performance, the optimal backwash cycle was obtained through the nutrient solution recycling system.