The purposes of this research were to study the effect of the concentration and soaking time of cassava in Ca(OH)2. The benefit of this research was to add a various type of food and to improve economic value. The design of experiment that used was a factorial design (3 x 3) in randomized group design with three times replication. Variable that used were concentration Ca(OH)2 (0,05%, 0,1%, and 0,15%) and soaking times (20 minutes; 30 minutes; and 40 minutes). The analysis parameters of this research were moisture content, ash content, starch content, fat content, and organoleptic test including taste, flavour, crispness, and colour. The method were cleaning, slicing, soaking, blanching, drying, and fiying.The result of this research based on scoring test to the cassava stick showed that cassava stick with code a2d2 was an interaction of 0,1% Ca(OH)2 and 30 minutes soaking time,was the best product with water content 2,13%, ash content 1,19%, starch content 33,38% and lipid content 3,69%. Kata Kunci : konsentrasi, perendaman, Ca(OH)2, Stick Ubi kayu.