A new technology for chaotic Brillouin optical correlation domain analysis (BOCDA) has been proposed and experimentally demonstrated with high spatial resolution. However, the off-peak amplification induced by the chaotic autocorrelation sidelobes limits the measurement range of chaotic BOCDA system. The time-gated scheme is introduced to suppress the off-peak amplification. With the pump pulse of 120 ns duration, the time-gated chaotic BOCDA has been experimentally achieved with a 9 cm spatial resolution over a 10.2 km measurement range. The standard deviation in the local Brillouin frequency shift is ± 1.8 MHz.