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Unique-structured composite microspheres of carbon and MoTe 2 were prepared by a two-step process. Precursor C-MoO x composite microspheres were prepared by spray pyrolysis, and then the precursor was transformed into C-MoTe 2 composite microspheres by a tellurization process. C-MoTe 2 composites with a uniform distribution of MoTe 2 nanocrystals (C/MoTe 2 ) and core-shell-structured C-MoTe 2 composites (C@MoTe 2 ) were synthesized at tellurization temperatures of 450 and 600 °C, respectively. At a higher tellurization temperature of 600 °C, all of the MoTe 2 nanocrystals moved to the surface of the microsphere because of the Ostwald ripening process. The initial discharge capacities of the C/MoTe 2 , C@MoTe 2 , and bare MoTe 2 (i.e., containing no carbonaceous materials) powders for Na-ion storage at a current density of 1.0 A g -1 were 328, 388, and 341 mA h g -1 , respectively. The discharge capacities of the C/MoTe 2 , C@MoTe 2 , and bare MoTe 2 powders for the 200 th cycle were 241, 286, and 104 mA h g -1 , respectively, and the corresponding capacity retentions, which were measured from the second cycle were 100%, 99%, and 37%, respectively. The high structural stability and well-developed two-dimensional layer of MoTe 2 of the C@MoTe 2 microspheres provide superior Na-ion storage properties compared to those of the C/MoTe 2 microspheres and bare MoTe 2 powder.