The invention relates to a water suspension 
pesticide containing pymetrozine and 
fenobucarb and a preparation method thereof. The rate of the pymetrozine to the 
fenobucarb is 1:0.5 to 1:8, and the pymetrozine and the 
fenobucarb account for 8% to 40% of the proportion by weight in the formula in total. The water suspension 
pesticide also comprises 1% to 10% of dispersing agent, 0.5% to 5% of 
wetting agent, 0.1% to 1% of thickener and suspension stabilizer, 1% to 5% of freeze proof agent, 0.1% to 1% of 
defoamer and the balance of water and is prepared in the following steps of filling the measured pymetrozine, fenobucarb, dispersing agent, 
wetting agent, freeze proof agent and water into a reaction kettle; 
cutting for 10 to 40 minutes; 
grinding for two to four times by adding the measured 
defoamer; adding the measured thicker, and 
cutting for 10 to 30 minutes. The 
pesticide of the invention overcomes the defects of weak pest defeat performance by independently using the pymetrozine and short effect time of the fenobucarb, and has the advantages of low cost, good effects for killing brown 
plant-hoppers and striped rice borers, no 
powder dust flying and no environment 
pollution.