In view of liquid steel flow in mould for C C alloy steel billets,the flow velocityof fluid in the different zones in the vicinity of vertical wall on condition of four hole nozzle hassystematically been measured by Laser Doppler Anemometre(LDA).At the same time,according tothe logarithmic wall law,logarithm ic wall law equations near by differen t wall zones and ex-periemental constan ts have been derived by regression method,The velocity distriution law near bywall in mould is obtained.