Rhenium disulfide (ReS2) is attracting more and more attention for its thickness-depended direct band gap. As a new appearing 2D transition metal dichalcogenide, the studies on synthesis method via chemical vapor deposition (CVD) is still rare. Here a systematically study on the CVD growth of continuous bilayer ReS2 film and single crystalline hexagonal ReS2 flake, as well as their corresponding optoelectronic properties is reported. Moreover, the growth mechanism has been proposed, accompanied with simulation study. High-performance photodetector based on ReS2 flake shows a high responsivity of 604 A center dot W-1, high external quantum efficiency of 1.50 x 10(5) %, and fast response time of 2 ms. ReS2 film-based photodetector exhibits weaker performance than the flake one; however, it still demonstrates a much faster response time (approximate to 10(3) ms) than other reported CVD-grown ReS2-based photodetector (approximate to 10(4)-10(5) ms). Such good properties of ReS2 render it a promising future in 2D optoelectronics.