In a modulation retro-reflector free-space optical (MRR FSO) system, the laser signal is severely affected by two-way atmospheric turbulence during transmission,causing the sys tem′s bit error rate performance to deteriorate.This paper proposes to adopt a low-density parity check (LDPC) met hod to reduce the bit error rate of the MRR FSO communication system.At the same time,experiments have also tried to u se microcorner cube retroreflector arrays (MCCRA) to improve the transmission stability of MRR FSO c hannels.In this study,we built MRR FSO communication experiment platform,and we did a frequency division duple x MRR FSO communication experiment based on LDPC coding.The experimental results show that the MRR FSO system using the LDPC coding method has a gain of about 3dB compared to the system using the common coding m ethod and the use of a micro- corner prism array as the MRR FSO reflective device can resist the effect of atm ospheric turbulence on the laser signal to a certain extent.The results also prove that LDPC coding can improve the bit error rate performance of MRR FSO system more than MCCRA.It can be seen that the combination of the LDPC codi ng method and the microcorner cube retroreflector arrays used in the MRR FSO system can obtain more optimized system performance.