To evaluate the change of low-temperature hydrothermal process on the characteristics of spent coffee grounds (SCG) and the performance after incorporation into concrete, the experiment of hydrothermal temperature and times was designed and carried out to incorporate the prepared spent coffee grounds hydrothermal biochar (SCG-HTC) as fine aggregate into concrete in the study. The study carried out to assess the varying SCG-HTC characteristics, SCG-HTC concrete performances and economic benefits through a methodological approach covering microstructure, workability, mechanical and thermal performance. The effects of hydrothermal times and temperature on the characteristics of SCG-HTC and the performance of SCG-HTC concrete were revealed. The results showed that the increase of both hydrothermal times and temperature significantly enriched the pore structure of SCG-HTC and changed the morphology of SCG-HTC particles. With the increase of hydrothermal temperature and times, the workability of SCG-HTC concrete gradually deteriorated, the mechanical performance first increased and then decreased, the thermal insulation performance and the ability to resist temperature changes improved. The appropriate substitution amount of SCG-HTC was not more than 15 %, and the cost of concrete could be reduced by 5 %∼7 %.