Competition in the business world is increasing with many businesses established with their own characteristics. In the era of increasingly fierce business competition, business actors in the culinary sector are especially required to implement marketing strategies that are not only effective but also in accordance with Islamic values. Muncul Jaya restaurant, which is one of the MSMEs in Semarang, certainly has its own marketing strategy in promoting its business. The strategy carried out must apply the principles or guidelines of good and healthy competition. The application of Islamic business ethics in marketing strategies is a crucial element that must be considered by business actors to achieve sustainability and build consumer confidence. This study aims to determine the marketing strategy applied by Muncul Jaya restaurant in increasing sales competitiveness and to determine the extent of the suitability of marketing strategies applied with the principles of Islamic business ethics. The research method used is an exploratory descriptive qualitative method with data collection techniques through observation, interviews, and documentation. Data analysis is conducted using ATLAS.ti. The results of this study indicate that the marketing strategy applied by Muncul Jaya restaurant is a marketing mix strategy by prioritizing 4P, namely Product, Price, Place, and Promotion. The principle of Islamic business ethics is the main foundation in restaurant operations. The conclusion of this study is that the application of marketing strategies based on Islamic business ethics not only increases business competitiveness but also creates a better relationship between the restaurant and its customers.