Abstract: OBJECTIVE To observe the therapeutic effects of nano-lanthanum hydroxide(Nano-LH) on hyperphosphatemia rats, and to compare the therapeutic effects with lanthanum carbonate and common particle size lanthanum hydroxide. METHODS A synthetic process of Nano-LH was established. Animal model of hyperphosphatemia in 60 Wistar rats with chronic renal failure was established by adenine(0.2 g·kg^-1), and the model rats were randomly divided into high, middle and low dose groups of Nano-LH(0.15, 0.1, 0.05 g·kg^-1), lanthanum carbonate group(0.3 g·kg^-1), normal particle size lanthanum hydroxide group(0.1 g·kg^-1) and model group. Another 20 Wistar rats were randomly divided into blank control group and blank administration group of Nano-LH. Biochemical indicators such as serum phosphorus, urine phosphorus, serum creatinine(Scr), urine creatinine, blood urea nitrogen(BUN), urine urea nitrogen, kidney index(KI) and parathyroid hormone were examined and the therapeutic effects of Nano-LH and common renagel on hyperphosphatemia were compared. RESULTS Compared with the model group, Nano-LH(0.1 g·kg^-1) had a lowering effect on serum phosphorus, Scr, BUN and KI in the hyperphosphatemia rats with significant differences(P<0.05). And it had a lowering effect than lanthanum carbonate and normal partical size lanthanum hydroxide, but there was no significant difference. CONCLUSION Nano-LH has higher potency than lanthanum carbonate, and can be a new phosphorus binder developed later.