Halmø

{{Infobox islands|name=Halmø|country_admin_divisions_title=Region|ethnic_groups=|density_km2=|population_as_of=|population=|country_leader_name=|country_leader_title=|country_largest_city_population=|country_largest_city=|country_capital_city=|country_admin_divisions_2=|country_admin_divisions_title_2=|country_admin_divisions_1=Ærø Municipality|country_admin_divisions_title_1=Municipality|country_admin_divisions=Region of Southern Denmark|country=Denmark|image_name=Halmø.1.jpg|nickname=|image_caption=Halmø seen from Ommel|image_size=|map=Denmark Region of Southern Denmark|native_name=|native_name_link=|location=|elevation_m=|coordinates={{coord|54|53|18|N|10|29|42|E|display=inline,title}}|archipelago=South Funen Archipelago|total_islands=|major_islands=|area_km2=0.5|highest_mount=|additional_info=}}

Halmø is a small private uninhabited Danish island in the South Funen Archipelago, lying 4 km northeast of Marstal. The island is 2 km long, and about 350 meters wide.{{Cite book|title=Danmarks Småøer|publisher=Politiken Håndbøger|isbn=87-567-6065-5}}