An analog optical fiber transmission system was developed for pulse signal transmission.The pulse electric signal was converted to optical signal by means of electro-optic conversion.After long distance transmission,the optical signal was recovered b y means of photo-electric conversion.The focus of the paper is on the modulation mode of the laser,the temperature control technique without dead zone and the balanced-PIN detector w ith dark current correction.The experimental measurement results of the system indicate that its bandwidth is DC~155MHz,linear dynamic range is 40dB,output peak-to-peak noise is less tha n 3mV.The results show that the system is suitable for scientific research with high requi rements on transmission bandwidth and security.