This study reports a flexible carbon nanotubes' (fCNTs) photosensor for light detection. The fCNTs photosensor is batch-fabricated using micromachining processes. In this device, CNTs (carbon nanotubes) are embedded into the flexible Parylene-C film using a batch micromachining process. Through this fabrication process, CNTs act as the component for light detection, and Parylene-C provides the flexibility of the device. In application, the fCNTs photosensor is implemented. The photocurrent response measurements indicate that the presented fCNTs photosensor operated as a function of heterostructure interface, pressure, light intensity and bias voltage under red laser illumination. The quantum efficiency of the fabricated fCNTs device is about 0.063% at atmospheric pressure, and becomes 1.93% in a vacuum of 3 mTorr. Thus, the presented fCNTs device has the potential for photosensor application. The position detection of a light source using the fCNTs photosensor array has also been demonstrated.