Coastal food services are an important segment within sea and sun' tourism. They have a direct impact on the environment from liquid and solid waste generation, air contamination, and excessive energy and water consumption. Mass tourism and the contemporary threat of climate change enhance the anthropogenic intrusion, especially in vulnerable coastal zones. To prevent overexploitation of the coastal zones, the adaptation of the sustainable principles by coastal stakeholders is an urgent matter. Thus, this study aims to design a model of sustainable development for restaurants and to examine the level of its adoption by seaside restaurant owners in two touristic beach areas of Cadiz province, Spain. A questionnaire was performed during the high summer season in 2018. The obtained data was analysed by IBM SPSS software. The survey results showed that the model of sustainable development has been poorly adopted by restaurant managers. Foreign managers of international restaurants are less involved in the adoption of the sustainable model in comparison to Spanish restaurant owners. Moreover, restaurants that have been opened more than 10-20 years provide a more sustainable way of business operation in comparison with newly established food service organizations.