According to US News, the referendum's goal is to change the definition of marriage in the Romanian constitution to a union between one man and one woman. This would effectively deny same-sex couples the right to marry as their union would not be recognized under the law.
Over three million signatures in favor of this change have been collected and with three million more, the referendum will be valid.
Romania is an eastern European country with a strong Orthodox Christian influence, which creates obstacles for people in favor of marriage equality. However, there are human rights groups that protest this referendum, saying that "human rights should not be put up for a vote."
Belgium, Denmark, Finland, France, Germany, Iceland, Ireland, Luxembourg, Malta, Netherlands, Norway, Portugal, Spain, Sweden, and the United Kingdom are the European countries that recognize same-sex marriage. Unfortunately, if the referendum passes, Romania will never join those countries in regard to marriage equality.
1May include recent laws or court decisions which have created legal recognition of same-sex relationships, but which have not entered into effect yet. (wikimedia.com)
h/t: US News