Abstract: The paper conducted the micro-aerated aged refuse reactor for leachate treatment and studied the longterm effect of hydraulic loading on leachate treatment． Ｒesults indicated that with the increase of hydraulic loading，the degradation of organics and nitrogen pollutants from leachate were reduced． In the stable stage，when the hydraulic loading reached 28，42， 56 L/( m3·d) ，the average COD removal were 88%，66%，56%，the average NH+ 4 －N removal were 94%，90%，71%，the average TN removal were 52%，50%，45%，respectively． However，once the hydraulic loading more than 42 L/( m3·d) ， the nitrite accumulation would appear and trend to be more serious with greater hydraulic loading． As a result，a proper hydraulic loading less than 42 L/( m3·d) was suggested during the leachate treatment by the micro-aerated aged refuse reactor．