The first six men across the line all set personal bests on a day of fine performance despite the changeable weather conditions in the capital.
Lel, Wanjiru and third-placed Abderrahim Goumri broke away from the leading group with four miles remaining and came into Westminster Square together.
But, as in previous years, Lel's sprint finish proved the difference.
"I knew I had to use my experience today and if I made a mistake I would lose," he said.
Robinson ran a time of 2:13.11 - more than 40 seconds better than his previous best - to finish in 12th place, just behind Olympic champion Stefano Baldini.
Liz Yelling admitted it had 'hurt'
"I'm quite satisfied, I can only do my best," he told BBC Sport.
"It's mind-boggling when the leaders are running 2:05 but my job was to finish top Brit, to run a PB if possible and try to confirm my Olympic place which I think I've done, so it's a case of job done."
Yelling recorded a time of 2:28.33 to finish ahead of her British rivals.
"I'm delighted to break the two-and-a-half hour barrier," Yelling, who finished three places ahead of fellow Brit Hayley Haining, told BBC Sport.
"I'm not sure I ran the best tactical race but I decided to just race and see how much I had.
"There was a lot of pressure, and it was just a case of trying to keep it in perspective and not let it get to me."
Russia's Svetlana Zakharova was in second place behind Mikitenko's winning time of 2:24.14, while Ethiopia's Gete Wami took third.
Mikitenko only started running marathons last year
Mikitenko, who used to run for her native Kazakhstan before moving to Germany in 1998, was running only her second race over the marathon distance after her switch from the long distance track events.
She finished second to Wami in the Berlin Marathon last year, but the Ethiopian race favourite fell badly at a feeding station by Canary Wharf and was left limping for the remainder of the race.
Mikitenko looked strong throughout and made the decisive break with 5km to go as the rain fell.
"I knew from 30km I could win and whatever happened I could deal with it," said Mikitenko.
Zakharova finished runner-up for the third time after previous near misses in 2001 and 2002.
The race took a slight detour after reports of a gas leak at a pub near the halfway point, but an inspection saw the course subsequently restored to its original route.
Cannot play media. Sorry, this media is not available in your territory.
BBC Sport's marathon music montage
With more than 35,000 runners pounding the streets of London, the event was expected to raise millions of pounds for charity.
Several celebrity runners were among those taking part, including chef Gordon Ramsey, Hollywood actor Johnny Lee Miller, former EastEnders and Quadrophenia star Phil Daniels and TV actress Amanda Holden.
Olympic rowing gold medallist James Cracknell finished just inside three hours in an impressive display.
Six Masai warriors from northern Tanzania, running in their traditional robes and carrying shields, were also among the participants.
London Marathon leading results (men):
1. Martin Lel (Kenya) 2 hrs 5 mins 15 secs 2. Samuel Wanjiru (Kenya) 2:05:24 3. Abderrahim Goumri (Morocco) 2:05:30 4. Emmanuel Mutai (Kenya) 2:06:15 5. Ryan Hall (US) 2:06:17 6. Deriba Mergia (Ethiopia) 2:06:38 7. Yonas Kifle (Eritrea) 2:08:51 8. Felix Limo (Kenya) 2:10:34 9. Aleksey Sokolov (Russia) 2:11:41 10. Hendrick Ramaala (South Africa) 2:11:44
This page is best viewed in an up-to-date web browser with style sheets (CSS) enabled. While you will be able to view the content of this page in your current browser, you will not be able to get the full visual experience. Please consider upgrading your browser software or enabling style sheets (CSS) if you are able to do so.