To understand the impact of margin trading business on the security market volatility,we use the wavelet CCC-GARCH models to conduct an empirical research by taking the market trading data from April 2,2010 to July 21,2016 as the samples.The results show that the margin financing has a significantly positive relationship with the return and the trading volume volatility of security market,while the influence of short selling is not significant.Meanwhile,the influence of margin trading on market volatility is mostly driven by the high frequency signal,and the irrational behavior or noise tradin...