In recent years, landscape information modelling (LIM) has been widely applied in various aspects of landscape design due to its instant modelling and data analysis capabilities, particularly in enhancing the precision of grading design. This study uses a garden exhibition in central China as a case study to demonstrate the application of LIM in constructing digital terrain and creating comprehensive grading plan. Through this study, we demonstrate that LIM can effectively help designers to improve design quality and evaluate grading plans by quantifiable criteria during landscape design procedure, offering valuable insights for landscape grading practice.