To develop a practical portable embedded OTDR

this paper presents and implements a design scheme

in which Field Programmable Gates Array（FPGA） is adopted for data acquisition

accumulation and averaging and ARM for human-computer interaction and data analysis.It briefly introduces the system working principle and hardware and software design

with emphasis on the FPGA procedures.The experimental results show that this design converges the characteristics and advantages of above two chips and enormously improves the system performance.