The American beat stage one winner Luka Mezgec (Giant-Shimano) into second and Nikolas Maes (Omega Pharma-Quick Step) into third.
The result means Farrar avoids finishing the season winless, and is his first WorldTour victory since his Tour de France stage win in 2011.
Philippe Gilbert finished safely in the peloton to retain the overall lead, however looks certain to lose it on tomorrow’s mountain-top finish.
Today, was all about the sprinters. Farrar managed to win from a very unlikely position, starting his sprint some 13 riders down, but his acceleration on the far right-hand side of the road was matched by no-one.
Mezgec may regret leaving it so late to start his sprint, as he was never able reach maximum speed before reaching the line.
Caleb Ewan (Orica-GreenEdge), on the other hand, will regret starting his sprint too early. A long turn at the front from Daryl Impey had placed him in what looked like the perfect position, and he led the peloton as Team Sky also looked well positioned, with Edvald Boasson Hagen and Ben Swift both following Ewan’s wheel, but the latter lost his position leaving Boasson Hagen to contest the sprint.
The Norwegian came past Ewan’s wheel, but was swamped by Farrar and Maes to the right and Mezgec, Moreno Hofland (Belkin) and Maximiliano Richeze (Lampre-Merida) from the left on a wide finishing straight, and faded to sixth.
Tour of Beijing 2014, stage three: Yanqing to Qianjiadian Chao Yang Temple, 176km
1. Tyler Farrar (USA) Garmin-Sharp
2. Luka Mezgec (Slo) Giant-Shimano
3. Nikolas Maes (Bel) Omega Pharma-QuickStep
4. Moreno Hofland (Ned) Belkin
5. Maximiliano Richeze (Arg) Lampre-Merida
6. Edvald Boasson Hagen (Nor) Sky
7. Danny Van Poppel (Ned) Trek Factory Racing
8. Boy Van Poppel (Ned) Trek Factory Racing
9. Davide Appollonio (Ita) Ag2r
10. Caleb Ewan (Aus) Orica-GreenEdge all same time
16. Ben Swift (GBr) Sky at same time
Overall classification after stage three
1. Philippe Gilbert (Bel) BMC Racing in 11-07-35
2. Reinardt Janse Van Rensburg (RSA) Giant-Shimano at 5 secs
3. Rui Costa (Por) Lampre-Merida at 7 secs
4. Daryl Impey (RSA) Orica-GreenEdge at 9 secs
5. Jesus Herrada (Spa) Movistar at 10 secs
6. Luka Mezgec (Slo) Giant-Shimano at 11 secs
7. Pieter Serry (Bel) Omega Pharma-QuickStep at 11 secs
8. Sergei Chernetski (Rus) Katusha at 11 secs
9. Mikael Cherel (Fra) Ag2r at 11 secs
10. Warren Barguil (Fra) Giant-Shimano at 11 secs
21. Daniel Martin (Irl) Garmin-Sharp at 11 secs
22. Simon Yates (GBr) Orica-GreenEdge at 11 secs
American sprinter Tyler Farrar leaves Garmin-Sharp after seven years to join South African outfit MTN-Qhubeka
Second stage of 2014 Tour of Beijing shortened due to air quality as Philippe Gilbert takes charge on uphill finish