A flexible optical measuring device is laser rangefinder with flexible ranging direction which includes a TOF (time of flight) laser rangefinder, an optical fiber adapter and a dual branch flexible light guide. The TOF laser rangefinder includes a laser diode source, an optical receiver and a computing unit. The dual branch flexible light guide is disposed and connected the TOF laser rangefinder. Due to the flexibility of dual branch flexible light guide, the laser ranging direction can also achieve ranging in any direction. Its ranging curve line equation is highly linearity. The cofficient of determination (R2) is moer than 0.9. Therefore, this design has been presented to meet with requirement for measuring distance indeeds for many applications.