Almost one third of the total number of Roma population in Croatia lives in Medjimurje. Roma people in Medjimurje mostly belong to an ethnic group called Boyash, and first appeared in larger numbers in the mid-19th century - although there are earlier records due to the changes that affected the rest of Europe. This thesis is primarily a review of the impact that Roma population had on the County's positive demographic developments until the end of the 20th century, as well as of their role in contemporary demographic development marked by negative trends; but it is also a comparative analysis of certain structures of total and Roma populations. The research shows that the Roma population did not have a significant influence on general demographics until the beginning of the 21st century. Due to negative demographic trends among the indigenous population, the influence became greater as a result of extremely favorable demographic indicators among the Roma population, causing an increase of the percentage of Roma people in general population. However, due to extremely negative and slowly changing indicators in their economic and educational structure, further growth of the Roma population could cause problems in many areas.