The invasive whitefly (Bemisia tabaci) feeds on phloem sap and distributes harmful viruses, causing considerable crop losses. These insects have a severe danger on global food security and agriculture. Whitefly management is challenging and standard methods of control have several drawbacks. RNA interference (RNAi) appeared to be a fantastic tool for pest control. This method provides a direct mode of action on specific genes, allowing altering physiological systems that affect insect growth, development or feeding behavior. The cysteine protease genes were used to create four dsRNA fragments. For the oral administration of dsRNA, a simpler insect bioassay approach was established. The oral bioassay was performed by feeding 200 adult whiteflies on dsRNA mixed with an artificial solution. The dsRNA fragments were employed in three concentrations (5, 15, and 30µg/ mL). Every day for four days, the mortality of adult whiteflies was reported. After 96 hours of feeding on cysteine proteases dsRNAs conc 30 µg/mL, the average mortality percentage was 73.875% for treated insects compared to 11% for the control. Quantitative PCR analysis of the treated insects revealed a substantial decrease in cysteine protease transcript levels, with mRNA levels dropping by 35, 2.11, 5.24, and 6.779 times as a result of cathepsine L cysteine proteases genes fragments A, B, C, and D dsRNA, respectively. The expression of cysteine protease dsRNAs in transgenic plants for whitefly protection might be an intriguing use of this technology.