In order to further improve the sensing performance of biosensors, a dual-core symmetric D-type photonic crystal fiber （PCF） sensor based on the surface plasmon resonance（SPR） effect is designed. The sensor is prepared by stacking, stretching and chemical vapor deposition （CVD） technology, and has two different diameter pores, and the two kinds of pores are symmetrical. The principle of glucose concentration detection system based on the sensor is introduced. The effects of metal materials, stomatal parameters and polishing parameters on the performance of the sensor are simulated and analyzed. The simulation results show that when the refractive index detection range is 1.26~1.41, the maximum wavelength sensitivity, resolution and glucose concentration detection sensitivity of the sensor can reach 24 600 nm/RIU, 4.06×10-6 RIU and 2.73 nm/（g·L-1） respectively.