AIM: To investigate differences in vaccination coverage between Roma and otherwise comparable non-Roma children, including factors associated with the vaccination gap, health care access and discrimination faced by Roma.<br/> METHODS: We analyse data from the Roma Regional Survey 2011 implemented in twelve countries of Central and South-East Europe. Our sample comprises 8233 children aged up to 6 with 7072 Roma children and 1161 non-Roma children. Estimates of the Roma vaccination gap are estimated using Logit regressions.<br/> RESULTS: We find that the Roma children have a lower probability of being vaccinated compared to non-Roma (odds ratio=0.325). The odds of being vaccinated for a Roma child is 33.9% that of a non-Roma child for DPT, 34.4% for Polio, 38.6% for MMR and 45.7% for BCG. These differences do not appear to be explained entirely by their worse socio-economic status. The ethnic gap narrows by about 50% once individual characteristics are controlled for, with odds ratios of 0.548 for DPT, 0.559 for Polio, 0.598 for MMR and 0.704 for BCG. The probability of being vaccinated increases with access to health care, especially when Roma have a doctor to approach when needed.<br/> CONCLUSIONS: Our findings point out a large difference in vaccination coverage between Roma and non-Roma and support the need for better understanding of factors influencing vaccination among Roma as well as policies that might improve services for Roma in Central and South-East Europe.<br/>