The 400 metres hurdler was voted into the role by her fellow team members.
She said: “I’m absolutely chuffed to bits. It’s a huge honour to have been elected by my peers as the team captain for British Athletics at London 2017.
“To lead your team at a home World Championships is truly a once-in-a-lifetime opportunity and to have your team-mates vote that they want you to do it makes it even more special.”
The Scot is a two-time outdoor world medallist in the 4x400m relay and also won bronze in the event at the Rio Olympics last year.
British Athletics performance director Neil Black said: “I’m delighted for Eilidh. She’s a fierce competitor and a fantastic role model for younger athletes in the team.
“Eilidh is Scotland’s most decorated athlete and has won a medal at all of the majors. She knows what it takes to win. That’s the type of athlete and mindset we need to lead us into a home world championships.”
The World Championships get under way at the London Stadium on August 4.