He beat Layla Moran in the contest, being held after Jo Swinson lost her seat in December's General Election.
In a speech, the new man in charge said the party must "change" to get back support of the British people.
Speaking to Jackie's Luke Williams last month, Sir Ed was sure he could lead the party to success.
Sir Ed’s leadership rival Layla Moran has paid tribute to his campaign.
Thank you so much to all my campaign team and volunteers. I am so proud of the positive, inclusive campaign we ran. I hope you’ll all join me in supporting @EdwardJDavey as our new leader. pic.twitter.com/IUUBDFCH9n
— Layla Moran 🔶🟡 (@LaylaMoran) August 27, 2020