To explore the application possibility of kidney injury molecule-1 (KIM-1) as a specific biomarker in the evaluation of the renal function, we studied the changes of kidney injury molecule-1 content and its mRNA level in Zebrafish (Danio rerio) after aristolochic acid treatment. The results were compared with the phenotypic changes of Zebrafish. The larvae showed periocular and pericardial edema in a dose-response manner after exposure to aristolochic acid for 30 hours (Table 1). Although the incidence of edema in 0.5﹣5.0 μmol/L aristolochic acid treated groups had no significant difference compared with the control, the protein content and mRNA expression level of KIM-1 in larvae tissue were significantly higher than the control (Table 1, Fig. 1). The peak appeared in the 2 μmol/L aristolochic acid treated group (Fig. 2, 3). From the result we can conclude that KIM-1 is a more sensitive indicator for detection of renal injury, whose changes are earlier than the morphological changes in zebrafish.