The executions took place in Besi prison on the island of Nusakambangan early on Wednesday morning local time, local media reports say.
Among those executed were Australian nationals Andrew Chan and Myuran Sukumaran.
Australia had appealed to Indonesia to delay the executions, citing alleged flaws in how their case was prosecuted.
Nigerian, Brazilian and Ghanaian nationals were also among those put to death.
Earlier, the men's families were allowed to see them for the last time.
A Filipina woman was also due to be executed but was reportedly spared at the last minute.
Mary Jane Fiesta Veloso was spared after the person who allegedly recruited her to act as a drug courier surrendered to police, the Jakarta Post reports.
Indonesia has some of the toughest drug laws in the world and ended a four-year moratorium on executions in 2013.
