| The COVID-19 pandemic has significantly impacted human life, particularly consumer behavior and the purchase of products and services. This study intends to investigate the impact of the COVID-19 situation (COV) on sustainability knowledge (SK) and sustainable purchase decisions (SPD). It also examines the impact of sustainability knowledge (SK) on sustainable purchase decisions (SPD). In addition, the study analyzes how sustainability knowledge (SK) mediates the relationship between the COVID-19 situation (COV) and sustainable purchase decisions (SPD). The stimulus-organism-response theory was employed to create a theoretical foundation for the investigation. The proposed model was investigated, and hypotheses were evaluated using partial least squares structural equation modeling (PLS-SEM) on a survey sample of 257 Indonesian consumers. The findings imply that the situation during the COVID-19 pandemic significantly impacts people’s comprehension and awareness of sustainability. Furthermore, learning about sustainability is critical for influencing sustainable purchase patterns. This study contributes to the current body of knowledge and offers insights into applying stimulus-organism-response theory among Indonesian consumers. Findings from this study are critical for understanding the factors that promote sustainable purchase decisions, particularly in the context of the COVID-19 pandemic. The findings could be a significant resource for governments and businesses in Indonesia looking to encourage and improve sustainable purchasing habits. Furthermore, the findings of this study can serve as a guide for producers in Indonesia to create and market products that adhere to sustainable standards. |