Introduction: Herbal medicines are good alternative treatment for management of blood glucose level. One of the herbal medicines that have potential as anti-diabetic is palm juice (Borassus flabellifer). Objective: This study was aimed to determine the effect of sap palm (Borassus flabellifer) on the decrease of blood glucose levels in patients with pre-diabetic. Methods: Design of quasi-experimental with a randomized pre-test post-test control group design. The total sample was 50 people, divided into two groups: the sap palm intervention group and education of 25 people and the control group with the education of 25 people. Result: There was a decrease in blood glucose levels in the group that received sap palm interventions, and a significant difference between the groups that received sap palm interventions with the control group. Based on the results of the follow-up, there was a decrease in blood glucose levels every week between the intervention group and the control group. However, the reduction was greater in the group with sap palm intervention. Provision of sap palm for three weeks at a dose of 200 ml 2 times a day, such as a morning and evening after eating, proved effective in reducing blood glucose levels in patients with pre-diabetic. Conclusions: Sap palm can be used as an alternative herbal medicine for pharmacological therapy in pre-diabetic.