To provide a process for producing carbon black, capable of efficiently producing the carbon black having a small particle diameter and a sharp aggregate size distribution.

In this process for producing the carbon black, a raw material introducing means composed of (a) a tubular passageway means capable of being taken out and put in, (b) a raw material spraying nozzle, and (c) a heat-shielding cooling jacket is applied to a carbon black production oven, wherein the tubular passageway means (a) makes a carbon black raw material circulate, the raw material spraying nozzle (b) is joined to a downstream side of the tubular passageway means and formed into a tapered truncated conical shape at a tip part thereof, and the heat-shielding cooling jacket (c) has such an inner wall that at least a part thereof is engaged with a shape of the raw material spraying nozzle and further has a means for forming a space through which a cooling medium circulates outside the jacket. Further, introduction of a raw material oil into the production oven from the raw material introducing means is conducted from at least a point in a space of the oven into which the introducing means is inserted and the raw material introducing means is arranged so that a rate of increase of a gas flow velocity brought about by insertion of the means into the space is more than 11% and set to be a value in a specified range to 100%, when the rate is calculated by formula: [rate of increase of gas flow velocity in a magnetic space] (%)={[(flow velocity after the insertion)-(flow velocity before the insertion)]/(flow velocity before the insertion)}×100.