In order to extend the dynamic range of the Lidar measurement, a signal acquisition system based on simultaneous analog and photon counting fusion method is designed. The signal acquisition system is comprised of the universal data acquisition card and universal photon counter card, a dual-channel preamplifier which is designed for the simultaneous analog and photon counting measurement by using the technique of multistage amplification. A testing system is configured with a Lidar signal simulation device. According to the plateaus characteristics of the photomultiplier tube (PMT) and the differential pulse height distributions measured by the testing system, the supply voltage of the PMT and the discriminator level are selected. The performance of the analog channel and photon counting channel of the signal acquisition system and the practicability of gluing two channels are tested. Experimental results show that the designed signal acquisition system has better performance than TR20-160, the Lidar transient recorder from LICEL. The signals from two channels are suitable for being glued together, and the dynamic range of the Lidar signal acquisition system is extended by the gluing.