Randomly obtained slag specimens from three different blast furnaces were chosen for experimentation. The flow behaviour of these slags was assessed adopting the heating microscope route. The flow behaviour of the slags were expressed relating to the softening temperatures (ST) that indicated beginning of permanent distortion, the liquidus temperature (HT) indicating sluggish flow and the flow temperature (FT) at which movement of the slag occurred in the liquid state. The characteristic temperatures were different for the slags collected from different sources having different compositions. The slag from source 2 was seen to be the most favourable for the blast furnace process having the narrowest cohesive zone in the specific blast furnace and formed lower down the furnace. Such a slag ought to have ensured enhanced operating conditions in the particular furnace with an augmentation of hot metal quality.