Abstract: In order to clarify the variation of floods/drought and provide references for floods/drought monitoring and agricultural production in Chongqing, the author regarded Chongqing which was in the upper of the Yangtze River as the research object. And through applying the monthly TRMM 3B43 precipitation data to the single site Z-index method, the author monitored Chongqing floods/drought on the scale of year and month from 2000 to 2011 by building TRMM-Z index based on remote sensing date. At the same time, the author analyzed the reliability of the TRMM-Z index by using the meteorological station Z Index. The results showed that: (1) TRMM-Z index monitoring method had good applicability and accuracy in the regional floods/drought monitoring. The correlation coefficient between TRMM-Z index and meteorological station Z index was 0.87 on year scale and monthly scale was 0.85. Both indicators are passed P＜0.01 significance test. (2) In floods/drought characteristics, 2 droughts (drought, extreme drought and 2 floods (large floods, extreme floods) in Chongqing have occurred in 2000 to 2011. (3) Month floods/drought characteristics, TRMM-Z monthly index fluctuated up and down around the value 0, alternating droughts and floods. During the time, the strongest degree of drought was in December 2003 and its value was -1.878. The strongest degree of flood was in August 2006 and its value was 1.930. And the floods/drought statistics showed that floods (2.6 months in an average of a year) happened more frequently than drought (2.5 months in an average of a year). From the trends of floods/ drought, January, September and October showed a downward trend and the largest declined in January. However, floods/drought showed an upward trend in the rest of the month. In 2000-2011, the driest happened in July and August in 2006.