Abstract: Seedlings of Citrus reticulata cv. Chachiensis, C. reticulata cv. Ponkan, C. reticulata cv. Fuju, C. reticulata cv. Sichuanhongju, C. grandis cv. Wendanyou, C. limon cv. Eureka, C. sinensis cv. Xuegan, C. aurantium (from Hubei)、C. aurantium cv. Goutoucheng (from Zhejiang), C. limonia (red)、Poncirus trifoliata, and citramelo (P. trifoliata × C. grandis) cultivated in pots containing sand were fertilized daily for 3 months with quarter-strength Hoagland’s solution at an Al concentration of 0, 0.2, 0.6, 1.0 or 1.6 mmol/L from AlCl3•6H2O. The results showed that ‘Xuegan’, ‘Chachiensis’, ‘Ponkan’, ‘Fuju’, ‘Sichunongju’, ‘Eureka’ and P. trifoliata were relative aluminum (Al) tolerant, whose dry weight of roots, shoots and whole plants was not affected at the 1.6 mmol/L Al level; ‘Goutoucheng’, C. aurantium, C. limonia and citramelo were relative Al sensitive, whose growth of roots and/or shoots was inhibited at the 1.6 mmol/L Al level. ‘Wendanyou’ was the most Al sensitve of all these citrus species and cultivars and 0.2 mmol/L Al decreased significantly its dry weight of roots and whole plants. Al stress resulted in an increase in the ratio of root dry weight to shoot dry weight of ‘Chachiensis’, ‘Fuju’, ‘Sichunongju’, C. aurantium, and P. trifoliata seedlings, but did not affect sgnificantly the ratio of ‘Ponkan’, ‘Guotoucheng’, ‘Eureka’, C. limonia, ‘Wendanyou’ and citramelo seedlings. No significant difference was found in the ratio of root dry weight to shoot dry weight of ‘Xuegan’ seedlings among different treatments except for a significant dcrease in the lowest Al treatment.