Abstract: The contents of sugar and mineral elements were measured during development period in Ougan (Citrus Suavissima Hort. ex Tanaka) fruits， to explore the accumulation trend of sugar and mineral elements and provide theoretical basis for the nutritional regulation. The results showed that during the development of fruits， the soluble sugar content increased continuously， accumulated quickly after Sept. 2nd and reached 770% on Nov. 22nd. The reducing sugar content increased gradually and reached 307% on Nov. 22nd. The sucrose content decreased in the early phase and increased later， which began to increase rapidly after Sept. 2nd and reached 440% on Nov. 22nd. The N， P， K， S contents decreased， and the Ca and Mg contents increased in the early phase and decreased later. The accumulation of N， P and K elements presented upward trends all along， especially in the rapid accumulation period. The accumulation of them increased and occupied 7219%， 7599%， 6643% of the total accumulation amounts from Aug. 12th to Oct. 12th, respectively. The accumulation of Ca， Mg and S increased from Jul. 2nd to Sept. 22nd and did not change after Oct. 22nd. The results indicated that Ougan was the sucrose accumulating type， and multielements compound fertilizer and K fertilizer application should be increased before midAugust．

Key words: Ougan, sugar, mineral elements