The research aimed to investigate the effect of soil conditioner combined with organic fertilizer on nitrogen and phosphorus leaching loss in facility soil. Based on the positioning experiment，a leakage device was used to collect leaching water at a depth of 90 cm underground.The concentrations and total leaching losses of total nitrogen (TN)，ammonium aitrogen(HN4+-N)，nitrate nitrogen(NO^3--N)，total phosphorus(TP)，and water-soluble phosphorous(DP)in the soil leaching water of spring tomato and autumn celery in 2023 were measured to study the leaching loss patterns of soil nitrogen and phosphorus in different fertilization treatments(CK:no fertilization，OM:organic fertilizer，T1:organic fertilizer combined with low-dose conditioner，T2:organic fertilizer combined with high-dose conditioner).The results showed that，(1)The concentrations of NH4+-N and NO^3--N in the spring tomato irrigation solution were maintained at a high level in the early stage，peaked after flowering and fruiting，and then decreased.After 67 days，they fluctuated at a low level，and the DP concentration changed relatively smoothly，showing a trend of first increasing and then decreasing，reaching its peak between 50-67 days；The trend of celery changes in autumn was consistent with that of tomatoes，except for the peak time.(2)The total amount of nitrogen and phosphorus leaching in the four fertilization methods showed that CK3--N，TP，DP，and particulate phosphorus in the T2 treatment was 85.70，0.75，73.46，2.16，1.89，and 0.28 kg/hm²，respectively，which were reduced by 34.60%，51.92%，40.45%，8.57%，51.78%，and 22.22%，compared to the OM treatment.After the experiment，the TN and TP leaching rates of T2 treatment in tomato and celery experiments were 8.34%，5.10%，and 0.31%，0.38%，respectively，which were 32.57%，39.64%，and 55.07%，36.67% lower than those of OM treatment，respectively. (3)The cumulative leaching loss(y)of TN(TP)in the leachate of two different vegetable treatments was fit over time(x).The logarithmic equation(y=A+B lnx)showed a high degree of fit between the cumulative leaching loss of TN and time，while the power equation(y=axb)showed a high degree of fit between the cumulative leaching loss of TP and time.There were significant differences in the values of a and b among the treatments. In summary，the application of organic fertilizers combined with high-dose conditioners in facility soil could significantly reduce the leaching losses of soil TN，NH4+-N，NO^3--N，TP，and DP，lower the leaching rates of TN and TP，and reduce the risk of nitrogen and phosphorus leaching.