Nanotechnology is science, engineering and technology carried out at the nano level with matter with at least one dimension between 1-100 nm in size controlled at different levels. Today, nanotechnology has very important applications in the forest products sector. One of these applications is for the modification and improvement of materials such as paints/varnishes, glues, etc. used in the relevant sector. In this context, it is important to modify and develop water-based systems that cause the least harm to human and environmental health. In recent years, many studies have been carried out to modify and improve water-based systems with organic and inorganic nanomaterials. Studies carried out with nanocellulose, which is environmentally and human friendly, which will minimize the harm of water-based varnish systems to human and environmental health, are of particular importance. The aim of this study is to review the academic studies on water-based varnishes modified with nanocellulose, an environmentally friendly nanomaterial, and to present and discuss the important results obtained and to develop various suggestions. As a result of the studies examined; it was observed that nanocellulose and its derivatives improve the optical, surface, physical and mechanical properties of water-based systems in wood materials from layer properties, and make them resistant to the effects of chemicals and aging.