The Spartacus Gay Travel Index 2019 puts France in 17th place, down from sixth place a year ago.
Canada, Portugal, and Sweden are the friendliest countries for LGBT travellers and they took joint first place in the latest edition of the guide.
Thirteen countries, most of them in Europe, tied for fourth place.
The reasons for France's dramatic fall were a rise in homophobic attacks and the postponement of parliamentary debates on bioethics laws, notably on assisted procreation, which is currently limited in France to heterosexual couples.
The Spartacus index ranked 197 countries based on 14 criteria, including anti-discrimination laws, marriage and civil partnership laws, adoption laws, transgender rights and persecution.
The United States dropped from 39th place to 47th.
Chechnya was ranked last of the 197 countries listed by the Berlin-based Spartacus guide, which provides tips for gay travellers on its website and mobile app.