With the advances in materials and integration of electronics and thermoelectrics, the demand for novel crystalline materials with ultimate high/low thermal conductivity is increasing. However, search for optimal thermal materials is challenge due to the tremendous degrees of freedom in the composition and structure of crystal compounds and nanostructures, and thus empirical search would be exhausting.Materials informatics, which combines the simulation/experiment with machine 2 learning, is now gaining great attention as a tool to accelerate the search of novel thermal materials. In this review, we discuss recent progress in developing materials informatics for heat transport: the exploration of crystals with high/low thermal conductivity via high-throughput screening, and nanostructure design for high/low thermal conductance using the Bayesian optimization and Monte Carlo tree search.The progresses show that the materials informatics method are useful for designing thermal functional materials. We end by addressing the remaining issues and challenges for further development.Nanostructure designing, Bayesian optimization, Monte Carlo tree search [6], ICSD [7], OQMD [8,9], and AtomWork [10], as shown in Fig. 1 (a). The thermal property of materials varies in a wide range. Taking thermal conductivity as an example, the order ranges from hundredths of Wm -1 K -1 to thousands of Wm -1 K -1 .Discovery of materials with very low or high thermal conductivity remains an experimental challenge due to high cost and time-consuming synthesis procedures.The other bottleneck is perhaps more challenging. As the length scale of materials decreases to nanoscale, heat conduction becomes more controllable through manipulating the nanostructures, as shown in Fig. 1 (b). Due to the various choices of structure parameters and coupled effects, it is difficult to quickly obtain the optimal nanostructure with desired thermal property from tremendous number of candidates.If exploring the materials or structures one by one using traditional heat transfer analysis method, it will become time-consuming and low-efficiency.The key next-generation technology to solve the above bottlenecks is materials informatics (MI): integration of material property calculations or measurements with informatics method to accelerate the material discovery and design [11][12][13]. During the past decade, MI has been successfully applied to design cathode materials of the lithium-ion battery, drugs, polymers, catalysis [14][15][16][17][18], and many others. The application of MI on thermal transport has also been gradually developed. In this review, we summarize the most recent progress of the MI application in heat transfer field. The review is organized as follows. In the first part, we summarize the recent progress of high-throughput screening for ultimate high/low lattice thermal conductivity materials. In the second part, we introduce the nanostructure