High temperature material properties of a welded joint were experimentally studied. Tensile and creep properties were measured for each part of weld metal. HAZ(heat affected zone) and parent metal at 538$^{circ}C$. HAZ metal was obtained by a simulated heat treatment. Results showed that the order of tensile strength is weld>HAZ> parent both at 24$^{circ}C$ and at 538$^{circ}C$. Creep resistance was also the highest for weld metal and lowest for parent metal. Creep rupture life curves were obtained and converted to Monkman-Grant relation which is useful for life assessment. Use of the data obtained in this study is discussed.