£13m of improvements have been made to the station, which had been closed for eight months, including:
The Mayor of London, Boris Johnson, said: 'Plaudits must be accorded to everyone involved with this project.
'Regular DLR users will have missed the station while it was shut but I know they will be pleased to discover an improved service upon their return.'
The re-opening of Tower Gateway also means DLR can now operate more trains to and from its new Woolwich Arsenal station.
During peak times there will be a train from Woolwich every five minutes, on average, instead of every seven.
Passengers will also be able to take a direct service from Tower Gateway to Beckton via the ExCeL exhibition and conference centre and the University of East London.
Jonathan Fox, Director DLR, said: 'Our new look Tower Gateway station includes many benefits for passengers and I am confident they will be impressed by its improved facilities and better accessibility.
'Furthermore passengers travelling to Woolwich via London City Airport will enjoy a more frequent peak service, while those heading to Beckton via ExCeL and the University of East London can take advantage of a swift, direct journey.
'It is particularly pleasing to see DLR once again maintain its record of delivering major projects ahead of schedule.'
Ian Brown, Managing Director London Rail, said: 'This is the first of a series of improvements being finished this year to pave the way for the introduction of three-carriage DLR trains before the London 2012 Olympic and Paralympic Games.
'Finishing Tower Gateway is key to our planning for growth on the DLR in the future.'
Notes to editors: