The rheology of polymer blends vary widely from that of the single components depending on their phase composition. The addition of carbon black makes the situation further complicated because of their related affinity towards the blend partners. Rheological studies are finding applications to understand the power consumption, machine dimensions, material properties, operational variables, faults and defects etc. Capillary flow is most useful method for understanding the flow properties for the polymer processing and shears rates. In this study the rheological behaviour of Natural Rubber (NR)/ Styrene Butadiene Rubber (SBR) blends have been studied in presence of High Abrasion Furnace Black (HAF) using capillary rheometry at different shear rates and temperatures. The preferential distribution of carbon black in the different phases has also been studied by varying the blending sequences. The four types of blending sequences have been considered as below, Blend-1: NR was masticated and mixed with SBR. The entire amount of HAF black was added to the Pre-blends.Blend-2: The entire black was added to the pre-masticated NR phase only. Then the black master batch was blended with fresh SBR.Blend-3: The entire black added to the SBR phase only. Then the black master batch was blended with pre-masticated NR.Blend-4: Half of the black was added to the pre-masticated NR and half of the black was added to SBR, then both the master batches are blended. The flow properties were determined by using the extrusion rheometry. When the carbon black preferentially in the SBR phase, the blend is most sensitive to changes in temperature and shear rates. Bound rubber changes as the sequence of blending changes. Black in the NR phase gives rise to higher viscosity. Flow activation energy decreases slightly at higher shear rates. Black in the SBR phase results in slightly higher flow activation energy than does black in the NR phase.There exists an exponential relationship between Mooney viscosity and low shear viscosity. Keywords: Flow behaviour, Capillary rheometry, Polymer blends, Bound Rubbers, Flow activation energy