Background: A woman with gestational diabetes needs to control her blood sugar in order to avoid problems such as high blood pressure, early delivery or the need for a caesarean delivery. The baby may be extra-large which will cause discomfort in the later stages of pregnancy and difficulties in delivering the baby. Objectives 1: To assess the blood sugar levels among mothers with Gestational diabetes mellitus. 2. To evaluate the effectiveness of intervention programme on glycemic control among mothers with Gestational Diabetes Mellitus. 3. To associate the effectiveness of intervention programme on glycemic control among mothers with Gestational Diabetes Mellitus with their selected socio demographic variables. Methods: An quantitative approach with quasi-experimental- design was adopted. 60 antenatal mothers from Vekatachalam Mandal, Nellore, A.P. by using non-probability convenience sample technique. Pretest and post test blood glucose score was assessedthrough glucometer followed by intervention programme. Results: The study Showed that, in experimental grou- pre-test 13(43.33%) had normal FBS and 17(56.66%) had hyperglycemia. Regarding PPBS, 6(20%) had normal PPBS and 24(80%) had hyperglycemia. Whereas in post test, 3(10%) had normal FBS. 27(90%) had hyperglycemia. Regarding PPBS 8(26.6%) had normal PPBS, 22(73%) had hyperglycemia. In control group in pre-test 15(50%) had normal FBS. 16(53.3%) had hyperglycemia? Regarding PPBS 7(23%) had normal PPBS, 23(76.66%) had hyperglycemia. Where as in post test 16(53.33%) had normal FBS. 14(46.66%) had hyperglycemia. Regarding PPBS 24(80%) had normal PPBS, 6(20%) had hyperglycemia. It is showing that Intervention programme on glycemic control among mothers with Gestational Diabetes Mellitus is more effective on glycemic control. Conclusion: The present study concluded that there was a significant difference between the pre test and post test of blood glucose level. Hence, it is concluded that, the Intervention Programme on glycemic control was effective in controlling the blood sugar level in mothers with Gestational Diabetes Mellitus.