Background: Nanohybrid composite resin is a restorative material in the field of dentistry that combines micro and nano-sized filler particles to enhance its mechanical hardness properties compared to its previous versions. Hardness can be influenced by several factors, including patients' beverage consumption patterns. A popular beverage among the Indonesian population is black tea (Camellia sinensis), which can be consumed both cold and hot. Objective: This study aims to determine the effect of beverage temperature on the hardness of nanohybrid composite resin. Methods: This study is a quasi-experimental laboratory study with a post-test only group design. The research sample consisted of 30 samples of nanohybrid composite resin with a diameter of 10 mm and a thickness of 2 mm, which were divided into three immersion groups: the control group using aquadest solution at 25±1°C, group I using black tea solution at 5±1°C, and group II using black tea solution at 50±1°C. The hardness of the samples was measured using a Vickers Hardness Tester. Data were analyzed using parametric One-Way ANOVA and Post Hoc LSD (Least Significant Difference) test. Results: The One-Way ANOVA analysis results showed a significant difference in the hardness values of nanohybrid composite resin after immersion in aquadest at 25±1°C, black tea at 5±1°C, and black tea at 50±1°C with a p<0.05. The Post Hoc LSD test results showed significant differences with a p<0.05 between the immersion groups. Conclusion: There is an effect of beverage temperature on the hardness of nanohybrid composite resin.