This study aims to determine the effectiveness of Nutrition Counseling with the CBT (Cognitive Behavior Therapy) Method on food waste and blood sugar levels compared to standardized nutrition consultations for DM patients at RSU Islam Klaten. This research is a quasi-experimental study with a cross-sectional approach and a pretest-posttest control group design. The sample of this research was 45 respondents who were divided into three groups, namely the nutrition counseling group using the CBT method, the standardized nutrition counseling group, and the control group. The data analysis test used the Mann Whitney test and the Wilcoxon test because the data were not normally distributed. The research results shownutritional counseling with the CBT method has a significant effect on the patient's food waste. This is evidenced by the results of the different tests before and after the CBT treatment showing a p value of 0.001, and the results of the different tests between groups, both in the CBT method nutrition counseling group compared to standardized nutrition counseling and in the CBT method nutrition counseling group compared to the control group, there was a significant difference with p values of 0.013 and 0.000 respectively less than 0.005.