Poly(2,5-dimercapto-1,3,4-thiadiazole) (PDMcT)/ sulfonated graphene conductive composite (PDMcT/SGS) was synthesized through in situ oxidative polymerization in the presence of the water-soluble sulfonated graphene sheets (SGS). Raman spectra revealed the existence of the p-p interaction between thiadiazole rings and basal planes of SGS. Scanning electron microscopy and transmission electron microscopy showed that the submicron-sized petals and nanofibers of PDMcT grew onto the surface of SGS. As evidenced by the cyclic voltammetry results, the incorporation of SGS has significantly improved the electrochemical activity and cyclability of PDMcT. The discharge capacity of PDMcT/SGS composite, measured with the charge-discharge tests, was 268 mAh g -1 at the first cycle and 124 mAh g -1 after 10 cycles.