We have developed a combinatorial pulsed laser deposition (PLD) combined with in-situ surface analysis techniques such as a scanning tunneling microscope (STM) and a low energy electron diffraction (LEED). Based on an atomically controlled PLD growth of an epitaxial anatase thin film, we have quickly screened transition metals of Ti to Cu deposited on the anatase TiO₂(001) surfaces by combinatorial approach. The behavior of transition metals on the anatase could be well understood in terms of the relationship between oxide formation enthalpy and surface diffusivity for each transition metal. Furthermore, after such an intensive screening experiment, we successfully discovered a new surface reconstruction induced by an impurity of Cr diffused into the bulk. The advantage of the combinatorial approach for surface science study is discussed.