Ground-based radar detection may act as a powerful means to determine the shape and physical properties of the asteroids in our Solar system. By measuring time delay and doppler frequency of the received echoes, radar systems provide information in ranging and radial velocity of the asteroids. Over the past few decades, more than 500 asteroids (mostly near-Earth ob jects) were detected using radar observations. There are two categories of radar detection: (1) The continuous wave detection, which is adopted to determine the roughness of an asteroid’s surface. (2) The delay-Doppler de-tection,which is likely to produce its three-dimensional model, and to define the rotational state. In the delay-Doppler detection, target asteroids are resolved in line-of-sight distance and line-of-sight velocity, providing two-dimensional images with spatial resolution as fine as meter-scale. Besides radar detection, several other techniques would also provide the shape model of the asteroids, among which the lightcurve inverse method is the most popular one to do that. In comparison with other methods, radar observation may have an advantage on spacial resolution. The lightcurves cannot reveal elaborate information on small features, and the intermediate-scale features of the inversed model are only suggestive. By contrast, radar detection produces resolved images. In this review, we present the radar observation technique and the method for recon-structing three-dimensional models of asteroids from radar measurements. In addition, we also provide several examples of asteroid models by radar detection, and then compare them with other observations for the shape reconstruction for the asteroids.%地基雷达探测是研究太阳系中小行星的重要方法。雷达探测主要有两种方式：(1)连续波探测，可得到小行星表面的粗糙度等参数；(2)延迟多普勒探测，用于反演小行星的三维形状模型并确定自转轴状态。与其他探测方法相比，雷达观测具有分辨率高等优势。简要介绍了地基雷达探测的原理和方式，以及通过雷达成像建立小行星形状模型的方法。同时举例说明了雷达探测小行星的成果，并对包括雷达在内的多种探测方法进行了比较。
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