As a new imaging technique——optical coherence tomography (OCT) has been widely used in clinical examination. However, the imaging speed and resolution are low. In order to improve the imaging speed and resolution, the sinusoidal-phase modulation OCT detection technology with a high-speed image sensor based on low-speed area array CCD is proposed. A piezoelectric transducer (PZT) is attached on the backside of Michelson interferometer′s reference mirror. A sinusoidal phase signal is used to control the movement of PZT, which makes reference mirror change its reference arm′s optical path as sinusoidal mode along the optical axis direction, thus scans sample′s depth. Light intensity expression of OCT interference signal is deduced, which is based on sinusoidal-phase modulation, and its imaging technology is discussed. One pixel on surface CCD can detect object′s internal fault structure, because PZT shifts phase continuously. Thus, this technique can get the information of sample′s internal fault structure using area array CCD. The technique does not need reference mirror with stepping movement and horizontal mechanical scan, it has lots of advantages, such as fast imaging speed, high sensitivity, high signal-to-noise ratio and low cost.