This study aims to explore and assess the reliability of a new landscape performance (LP) assessment framework (NF) with smart device assistance. Against the backdrop of rapid urbanization and the increasing severity of climate changes, and to prove sustainable values of landscape projects, LP is receiving more attention. However, some gaps exist and slow the development of LP research. such as only based on one-time measurement to assess projects’ LP, inconsistent methods involved in different LP research, and insufficient tools to measure LP metrics. To fill these gaps, the research team recently proposed and tested a NF with smart device assistance. Due to the relatively short development time, little research has been conducted to examine its reliability. Meanwhile, its potential strengths and limitations need more studies to explore fully. Thus, the research team employs the comparative research method, following traditional and new frameworks, to gather two sets of LP data for experimental sites. These two data sets are comparatively analysed to get solid data-driven results using statistical methods. Findings demonstrate the validity of the NF. Meanwhile, results demonstrate the capacity of this framework in terms of data comprehensiveness, data accuracy, and dynamic data reflecting LP. It also explores the limitations of the NF to a certain extent. This study can further develop and implement the NF in the LP field, contributing to addressing current gaps. Also, it contributes to enhancing LP assessment's accuracy, which not only benefits professionals and decision-makers by providing more valuable and reliable data but also increases public interest by increasing their trust in landscape project’s sustainable values.