Background: Antenatal healthcare providers’ (AHPs) knowledge about hyperglycaemia in pregnancy (HIP) and its screening best practices affect the management of affected pregnant women. We assessed the knowledge of HIP and associated factors amongst first line AHPs. Methods: This descriptive cross-sectional study involved 188 Doctors, Nurses and Community Health providers directly involved in providing antenatal care at all levels of health care in Jos, Plateau State, Nigeria, selected through total sampling technique. Result: A total of 103 AHPs (54.8%) were females. The mean knowledge score (SD) score was 17.0+/-5.5 (out of 30). Only 93 (49.5%) had a good knowledge of HIP (Knowledge score ≥18). Only 88 (46.8%) could correctly identify 75g OGTT or 100g OGTT as diagnostic tests for GDM. Gender, category of hospital, level of care of the institution and job designation were significantly associated with knowledge of HIP after bivariate analysis (p < 0.05). After multivariate analysis using logistic regression analysis, only the category of institution and job designation were independently associated with knowledge of HIP. Conclusion: The general level of knowledge of HIP among AHPs is average but awareness of testing and management guidelines is very poor hence the need for regular updates for health professionals. Keywords: Hyperglycaemia in Pregnancy; gestational diabetes mellitus; knowledge of GDM; guidelines for GDM.