Abstract: A large amount of power harmonic is generated due to the increase of nonlinear load in a power system. The power harmonic is harmful to the power system and instrument. However, harmonic analysis lays the foundation for power harmonic treatment. The paper discusses the development of a power harmonic analyzer based on DSP and LabVIEW, which is used to analyze and measure harmonic on real-time. The analyzer's hardware, harmonic analysis algorithm, LabVIEW software design and the implementation are all brought forward in detail. Experiments show that the analyzer has high measurement accuracy, good real-time performance, friendly man-machine interface and convenient system extension features.