Mesoporous, micro/nanosized TiO2/C composites with uniformly dispersed TiO2 nanoparticles embedded in a carbon matrix have been rationally designed and synthesized. In brief, TiO2 precursor was infiltrated into the channels of surface-oxidized mesoporous carbon (CMK-3) by means of electrostatic interaction, followed by in situ hydrolysis and growth of TiO2 nanocrystallites, resulting in ultrafine TiO2 nanoparticle confined inside the channels of mesopores carbon. After chemical lithiation and post-annealing, TiO2 nanoparticles were transformed in situ into Li4Ti5O12 to form highly conductivity mesoporous Li4Ti5O12/C composite, as confirmed by scanning electron microscope (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), Raman spectroscopy, and nitrogen sorption isotherms. By combining high electronic conductivity, open mesoporosity, and nanosized active material, coherent mesoporous TiO2/C and Li4Ti5O12/C nanocomposites demonstrated high rate capability and good cycling properties.