Hobart Bay is a census-designated place that was located in Hoonah-Angoon Census Area, Alaska during the 2010 United States Census, but is now part of Petersburg Borough. As of the 2010 Census, the population of the CDP was one.
The bay was named in 1889 by Lt. Commander Mansfield of the U. S. Navy. The site was first settled as a logging camp. The population has declined in recent years. Nevertheless, on January 3, 2013, Hobart Bay and a sizable portion of the Hoonah-Angoon Census Area around it were incorporated into the new Petersburg Borough, which has the city of Petersburg as its economic center and is composed primarily of land from the former Petersburg Census Area.