The MoS2 flakes are directly prepared on SiO2/Si substrates with chemical vapor deposition (CVD) in varied carried gas flow rate. It can be found that the monolayer and dendritic morphologies MoS2 flakes can be formed with different Ar flow rate, respectively. It demonstrates that the carrier gas flow rate has strong influence on the structure and morphology of CVD-grown MoS2 flakes, and consequently tailors the optical properties of MoS2 flakes significantly. These results pave the way for the development of CVD method with controlled growth parameters and opens up new venues for the synthesis of macroscopically uniform monolayer MoS2. (C) 2015 Elsevier B.V. All rights reserved.