Background: Blood glucose levels in patients with diabetes mellitus are sometimes unstable. This is one of them can be triggered by the level of stress on the person. This stress factor can be suppressed by raising the spiritual on itself, so that from this spiritual can make the patient feel calm and this can lower the patient's stress level. With the decrease in stress levels of patients it can lower blood glucose levels in these patients. Purpose: The aim of this research is to know the spiritual relation to fasting blood glucose in diabetes mellitus patient at PKU Muhammadiyah Gamping Hospital. Method: This research used correlational quantitative method with crossectional approach. The study was conducted with 28 respondents. Sampling technique with consecutive sampling. Data analysis used Pearson correlation test, research instrument used FACIT-Sp questionnaire and patient blood glucose data Results: The results of the study was the spiritual average of diabetes mellitus patients were 34.32 with range (0-48) and mean blood sugar 192,78 mg / dL. Based on bivariate statistic analysis used Pearson correlation got result (P value = 0,534). Conclusion: This research can be concluded that there is no relation between spiritual to fasting blood sugar in patients with diabetes mellitus in PKU Muhammadiyah Gamping Hospital.