Abstract: The number of light-vented bulbul(Pycnonotus sinens)from September 2004 to August 2005 in Nanchong area in Sichuan province were investigated.The results showed that the number of light-vented bulbul has grown significantly and become a dominant species since 1950’s.Parameters affecting the growth of Pycnonoutus sinens were analyzed and found that food,roost-site,laert distance,interspecific competition,and city lights are appropriate factor.Pycnonotus sinens has got used to the city life and be..