Introduction: Glucose testing at six weeks postpartum has been recommended by the World Health Organization as the earliest period in which to detect abnormal glucose tolerance among women with a history of gestational diabetes mellitus (GDM). This study aimed to determine the outcomes of six weeks postpartum glucose testing and its associated factors among women with a history GDM who attended government primary health clinics in Johor Bahru. Methods: The study was a cross sectional study which was conducted among women with a history of GDM who registered from January to June 2016 at primary health clinics in Johor Bahru and underwent an oral glucose tolerance test at six weeks postpartum. Secondary data were obtained from Maternal Health Records (clinic copy). Data were analyzed using SPSS Version 23.0. Descriptive statistics and simple logistic regression analysis were used. Results: One hundred and twenty-two women with a history of GDM completed the postpartum glucose testing. Approximately 12% of these women were reported to have abnormal glucose tolerance. Insulin usage (OR:5.44; 95% CI:1.53, 19.43; p=0.009), abnormal glycated hemoglobin (OR:8.70; 95% CI:2.68,26.27; p<0.01), hospital follow-up (OR:3.38; 95% CI: 1.11, 10.34; p=0.033) and neonatal intensive care unit admission (OR:3.96; 95% CI: 1.16, 13.54; p=0.028) were found to have significant associations with abnormal glucose tolerance at six weeks postpartum. Conclusion: The proportion of women with a history of GDM and abnormal glucose tolerance at six weeks postpartum in Johor Bahru was 12% and was associated with insulin usage, abnormal glycated hemoglobin, hospital follow-up and neonatal intensive care unit admission. Screening during the postpartum period offers a window of opportunity for early identification of diabetes and prediabetes, as women with history of GDM are at increased risk of future glucose intolerance.