As one of the world’s three major ecosystems, wetlands play an important role in maintaining ecological balance. However, in recent years, wetland resources have suffered from encroachment and frequent water environment and soil pollution problems, causing serious damage to China’s wetland ecosystem. The study proposes to conduct a performance audit (PA) of the wetland park project (WPP) using financial and accounting tools to assess the effectiveness of wetland restoration. The study first constructed a PA evaluation index system for WPP using the pressure-state-response (PSR) model to ensure the comprehensiveness of the evaluation indexes. Subsequently, grey relational analysis combined with analytic hierarchy process (GREY-AHP) was introduced to convert the scores into mutual inverse judgment matrices and assign weights to the indicators to improve the accuracy and scientificity of the construction system. Finally, the PA evaluation results are derived through comprehensive evaluation. The innovation of the study is to apply the PSR model to WPP’s PA, which significantly improves the accuracy and comprehensive performance of the evaluation compared with the traditional method. The experimental results show that the maximum F1 values of the research-proposed model on the test set and validation set are 95.2 and 97.6, respectively, which are higher than those of other algorithms, showing the advantage in comprehensive evaluation performance. The results of the study are of great significance for improving the performance level of WPP and effectively protecting and restoring wetlands.