BACKGROUND: Obesity and overweight are common issues for pregnant women and their healthcare providers. Obesity in pregnancy is associated with poorer maternal and perinatal outcomes and presents particular challenges in day-to-day clinical practice. QUESTION: The aim of this study was to examine midwifery clinical practice for obese pregnant women. METHODS: We conducted a cross-sectional survey of midwives using an on-line survey distributed to members of the Australian College of Midwives. Midwives were asked about: the extent to which they provided evidence-based care; their use of a clinical guideline; their education and training and confidence to counsel obese pregnant women. Data for the questions about knowledge, clinical practice and views of education and training were summarized using descriptive statistics. Unadjusted analyses were undertaken to examine the association between use of a guideline and provision of evidence-based care and ratings of education, training and counselling. RESULTS: The survey highlighted considerable variations in practice in the care and management of obese pregnant women. Respondents' clinical knowledge and their views about education and training and counselling skills highlighted some deficits. Those using a clinical guideline were more likely to report that they 'always': tell the woman she is overweight or obese (OR 3.5; 95% CI: 1.9, 6.4); recommend a higher dose of folic acid (OR 4.6; 95% CI: 1.9, 6.4); refer to an obstetrician (OR 2.9; 95% CI: 1.2, 3.4); prepare a pregnancy plan (OR 2.0; 95% CI: 1.2, 3.3) and plan to obtain an anaesthetic referral (OR 2.6; 95% CI: 1.5, 4.3). They were also more likely to report adequate/comprehensive education and training and greater confidence to counsel obese pregnant women. CONCLUSIONS: Registered midwives need continuing professional development in communication and counselling to more effectively manage the care of obese pregnant women. The universal use of a clinical guideline may have a positive impact by helping midwives to base early care decisions on clinical evidence.