Radio wave propagation error is the main factor affecting positioning and timing accuracy of the enhanced loransystem.Based on the analysis of Loran-C positioning error, the basic principle and system composition of using differential loran isproposed to improve the local domain performance, the realization approach of differential correction generation, differentialmessage transmission based on Loran Data Channel (LDC), differential message design and user differential processing are discussedin detail, and the differential loran technique system and performance improvement effect through experiments are validated.It lays atechnical foundation for the engineering application of enhanced loran system.