This research is aimed to study the effect addition of Borax on Vulcanization properties of Rubber. which is represented by Viscosity , Elasticity,Plasticity which is defined as Rheology where suitable Quantities from Borax powder with loading level (0,5,10,15,20 pphr) were added to suitable type of Rubber (styrene- Butadiene Rubber, Nitrile Rubber ,and poly Chloroprene type (WRT)) and notice the change in Scorch time and this perioed time which is limited the Resistance of Rubber Compounds to Vulcaniztion and Occurrence at Min. point of Viscosity and Curing time which is Limited the Perioed time for Ending the Vulcaniztion Process and Occurrence at atopmost point for Viscosity after addition of Borax to Rubber Compounds and which has been check that the addition Borax powder which is discrease the Viscosity of (SBR ) Rubber and Increase the Viscosity of (NBR) Rubber and Increase the viscosity of (WRT) Rubber for point (10pphr)