The 230 nm far-UVC LED packaging device was fabricated， and the influence of the photoelectric performance and reliability by using fluorine resin for packaging were studied. The results showed that the optical power of 230 nm far-UVC LED packaging device with fluorine resin had a increase of 13%， which could reach 1 mW， and no influence was found in aging performance， while the photoelectric conversion efficiency was still less than 0.1%. After 216 h normal temperature aging， the light maintenance rate decreased to 45%. The application of 230 nm far-UVC device for detection of nitrate concentration was also evaluated. The results showed that when the concentration was lower than 15 mg/L， the absorbance in cm^-1 showed a linear relationship with the concentration of the nitrate solution， which indicated that the 230 nm far-UVC device could be used in nitrate determination.