The graphitic carbon nitride (g-C 3 N 4 ) was treated via alkaline hydrothermal treatment to change the porous structure of g-C 3 N 4 to "tube-like" structure. The developed alkaline treated g-C 3 N 4 (A-g-C 3 N 4 ) was combined with P25 Degussa TiO 2 for the competent removal of methylene blue (MB). The morphological changes increased the crystallite size and pore size of g-C 3 N 4 , causing a decrease in the specific surface area of A-g-C 3 N 4 . The pure g-C 3 N 4 demonstrated the best degradation efficiency among the all samples due to its high specific surface area, low band gap energy and small pore size. The combination of both A-g-C 3 N 4 and g-C 3 N 4 with TiO 2 did not exert significant effect on the degradation efficiency of MB owing to the low specific surface area, high band gap and large pore size. Thus concluding the degradation efficiency of organic dye is attributed predominantly to the factors of energy band gap, specific surface area and pore sizes.