Substrate heating is one of the viable measures to alleviate thermomechanical issues and, more importantly, microcracking in high-strength superalloys by laser powder bed fusion (LPBF). However, most research reported so far focused on LPBF systems of substrate temperature only up to 200 degC, a relatively low temperature for superalloys (<0.3 homologous temperatures). To improve the processibility and broaden the range of superalloys for LPBF, we explored the effects of substrate temperature up to 500 degC regarding the impacts on surface quality, deformation, and microstructure. Significant differences in crack susceptibility, phase precipitation, and microstructural deformation were observed, but the impact on surface roughness is moderate. The findings in this study will be explained in terms of metallurgy, microstructural analyses and process modelling. This presentation aims to provide scientific references for the benefits and issues of using high substrate temperature on superalloys by LPBF.