Carbon black (CB) was encapsulated with branched poly(styrene-alt-male anhydride) (BPSMA) by phase separation method for use in textile printing. Experimental results showed that, when BPSMA was synthesized using a molar ratio of the chain transfer agent (4-vinylphenyl methanethiol) to monomers (styrene and maleic anhydride) at 6:94 and a mass ratio of the initiator (benzoyl peroxide) to monomers at 1:50, the encapsulated CB was constructed with a smallest particle size and as such a highest stability to temperature. An optimized BPSMA-encapsulated CB dispersion was achieved by adding BPSMA and CB at mass ratio of 1:5 and maintaining pH at 10. The BPSMA-encapsulated CB composite was characterized using Scanning electron microscope, Fourier-transform infrared spectroscopy, thermo gravimetric analyzer, and drop shape analyzer. The BPSMA-encapsulated CB dispersion was demonstrated to have an excellent performance for printing cotton fabric.