Abstract: Casing sidetracking short radius horizontal well technology comes into use to redevelop oil wells for developing efficaciously the reserver oil and irreducible oil in area uncontrolled,restoring and increasing per-well production and ultimate recovery.In 2004 and 2005,CNPC have had drilled successfully two well,NB31 and NB30,that are casing sidetracking short radius horizontal wells in North Buzachi shallow viscous oil reservoir of Kazakhstan.NB31 and NB30 gain high production after brought into production.This paper introduce the operation condition of the two well,wherein include optimization of well program,implementation of high kick-off rate in shallow viscous oil reservoir,compatibility analysis of the high bend angle PDM and wellhead,friction when casings run in short radius horizontal section and completing well technology etc. to provide successful experience for this technology applicating and expansion in North Buzachi oil field and domestic oil field.