Herein, a bioprobe based on hollow fibers with electrical and optical delivery channels is proposed to realize low attenuation transmission of mid-infrared light at the wavelength band ranging from 5 μm to 10 μm. Cyclic olefin polymer (COP) is used to isolate the front-end of the probe from water and the necessary sealing technology is designed and optimized. The loss of bioprobe with length of 20 cm and inner diameter/outer diameter (ID/OD) of 0.7 mm/1.5 mm is 1.38 dB at a wavelength of 5.1 μm. By controlling the sealing process, COP sealed windows with different shapes are fabricated to modify the output beam. The focal length and far-field divergence angle for these different configurations are analyzed by measuring the output beam profiles. This approach will provide more ways and means for neuroscience research and biomedical application.