Most big data are spatially referenced, and spatial data mining (SDM) is the key to the value of big data. In this paper, SDM are overviewed in the aspects of software and application. First, spatial data are summarized on their rapid growth, distinct characteristics, and implicit values. Second, the principles of SDM are briefed with the descriptive definition, fundamental attributes, discovery mechanism, and usable methods. Third, SDM software is presented in the context of software components, developing methodology, typical software for geographical information system (GIS) data and remote sensing (RS) images, and software trend. Fourth, SDM applications are outlined on GIS data, RS image, and spatiotemporal video data. The final is the concluding remarks and perspectives.