Public interest in information about the origin of products triggered the development of the concept of supply chain transparency, when products change ownership from supplier to manufacturer, no information is exchanged between the two parties. It is more proper to start with a firm's perspective in order to discuss the supply chain transparency more deeply, and then extend it to the supply chain. Firms are responsible for environmental and social issues within the sphere of action of their suppliers, and need to meet the challenges of transparency and compliance in the supply chain. Supplier audits are often criticized for lacking authenticity and objectivity, and supplier transparency assessments are central to achieving supply chain transparency. Moreover, there is still no independent standard framework for assessing transparency performance. This study attempts to develop a model for supplier evaluation considering transparency practices with the aim of increasing transparency practices when selecting suppliers. Transparency is a multidimensional concept with different meanings and functions. We interpret the meaning of transparency from the literature, analyze the advantages and needs of suppliers in supply chain transparency practices, and build a supplier transparency evaluation system by taking into account transparency practices. A comprehensive assessment framework is then proposed to unwind the impact of transparency on the three dimensions of sustainability, the neutrosophic set is used to deal with the uncertainty and inconsistency of information to improve the authenticity of information inputs. We have developed a new hybrid multi-criteria decision model for evaluating the transparency performance of suppliers, and checking the robustness of the assessment by using sensitivity analyses. This study quantifies the impact of suppliers on supply chain transparency and makes recommendations on how to make more effective and positive contributions to improving supply chain transparency through supplier management.