In nuclear accident radioactive dust,Cesium is one of the main nuclear.So establishing fast and effective detection of the cesium and other elements is an important research direction of nuclear accident emergency.This study establishes a collinear double pulses laser induced breakdown spectroscopy (DP-LIBS) technology of nuclide cesium detection method.Optimization experiment of gate delay time finds that the signal spectrum reach maximum enhancement,when the gate delay time is 2.0 ms.When the delay time between two lasers is 3.8 ms,the signal spectrum is best.Through the quantitative analysis of the leaf sample tablet,when the analysis line is CsI:894.3 nm,fitting coefficient R2 of fitting curve is 0.91.Further using DP-LIBS to analysis Photiniaxfraseri leaf which is dealt with different concentrations of Cscl,and the result shows that:leaf which is dealt with different concentrations of Cscl has obvious spectrum in CsI:894.3 nm,fitting coefficient of fitting curve is 0.73.The feasibility are proved that LIBS technology can achieve rapid detection of radionuclide cesium content in environment.