Abstract: H9N2 avian influenza virus is responsible for the majority of death in Iranian poultry farms due to renal damage. For understanding the nephropathogenicity of H9N2 avian influenza virus in commercial broiler chickens, thirty 20 days old chickens were intratracheally inoculated with 106 EID50 per bird with A/Chicken/Iran/SH-110/99 (H9N2) avian influenza virus. Then on days 1, 2, 4, 6, 8 and 10 Post-Inoculation (PI) samples of the kidney were collected for histopathologic studies. In inoculated chickens tubulointerstitial nephritis in the kidney were observed on days 6, 8 and 10 PI. The results indicated that the A/Chicken/Iran/SH-110/99 (H9N2) avian influenza virus after IT inoculation has pathogenicity for kidney (nephrotropic).