To realize multi-point velocity measurements in micro fluid flow, this paper presents a study on laser Doppler velocimetry based on the dual-core photonic crystal fiber. The coherent characteristics and property of measurement volume based on the dual-core photonic crystal fiber are theoretically analyzed. Calculation results show that there are five bright interference fringes in measurement volume as the spacing between two fiber cores is about 7.4 μm, which is in agreement with the experiments. Due to the noise in experiment, intensity ratio of each fringe in experiment is lower than that based on the calculation. Enlarging the spacing between two fiber cores results in the increase of interference fringes, thus leads to increase the accuracy of measuring velocity. According to the images during the process from two separated faculae to their interference, the working distance for this velocimetry can be identified as about 30 μm. The principle of multi- point measurements of laser Doppler velocimetry based on the dual-core photonic crystal fiber is analyzed. The test based on the velocimetry is then executed to measure the single point velocity, two-point velocities and three-point velocities. For single point measurement, the averaged velocity of the particle is 0.980 m/s with the relative uncertainty of 0.5%. For two-point measurements, the averaged velocities of the particles are 1.761 m/s and 1.769 m/s, respectively. For three-point measurements, the averaged velocities of the particles are 2.106 m/s, 2.084 m/s and 2.097 m/s, respectively. Experimental results demonstrates that the laser Doppler velocimetry based on the dual-core photonic crystal fiber can realize multi-point velocity measurements. The velocimetry has the advantages with micro sensing head and simple systematic configuration over classical one. Therefore, the velocimetry can be embedded in the micro system for multi-point velocity measurements of micro fluid flow.