The changes of plasma PTH, 1,25(OH)2D3, serum calcium, phosphorus and AKP were observed in 55 uremic patients with renal osteodystrophy. The results showed that: In all types of renal osteodystrophy, plasma PTH were markedly higher than normal (P < 0.001), while plasma 1,25(OH)2D3 and serum calcium were lower than normal (P < 0.001). In low bone-turnover uremic osteodystrophy (LTO), plasma phosphorus was markedly lower than that of high bone-turnover uremic osteodystrophy (HTO) and mixed uremic osteodystrophy (MO) (P < 0.05), and plasma 1,25(OH)2D3 was significantly lower than that of HTO (P < 0.05). In HTO and MO, serum phosphorus was much higher than normal (P < 0.001). Plasma PTH had a negative linear correlation with plasma 1,25(OH)2D3 (P < 0.05), a positive linear correlation with serum AKP (P < 0.05), but no linear correlation with the duration of hemodialysis, serum calcium, serum aluminum and bone aluminum content. Plasma 1,25(OH)2D3 had no linear correlation with the duration of hemodialysis, serum phosphorus, serum aluminum and bone aluminum content. There was no significant difference in the plasma PTH, 1,25(OH)2D3 and serum AKP between the bone aluminum stain positive and negative groups.