Goals from Jesse Lingard and Craig Dawson put the Hammers 2-0 up at half-time and Leeds then squandered several good opportunities after the break as the Hammers moved fifth.
The Whites have now gone 16 games without winning in the capital and Graham Smyth, the YEP's chief football writer, hands out the scores.
1. Illan Meslier
6 - Looked under real pressure at corners. Photo by ANDY RAIN/POOL/AFP via Getty Images.
2. Luke Ayling
5 - Gave away the penalty with a needless challenge. Didn't look at his best in the first half. Got forward well in the second half and created danger at least. Photo by IAN WALTON/POOL/AFP via Getty Images.
3. Liam Cooper
6 - Some solid, physical defending, some nice passing and some not so nice passing. Gave the ball away in the first half and West Ham countered to win a penalty. Photo by Ian Walton - Pool/Getty Images.
4. Diego Llorente
5 - Really struggled at set-pieces, wayward with some of his forward passes. Some nice moments though, the through ball for Bamford in particular. Photo by IAN WALTON/POOL/AFP via Getty Images.
5. Stuart Dallas
7 - One player who made a real impact, particularly in the second half from a midfield position. Gave Leeds presence and impetus that had been lacking. Photo by ANDY RAIN/POOL/AFP via Getty Images.
6. Kalvin Phillips
6 - Got in positions to progress the play but looked overrun in the first half. Decent performance overall. Unlucky to be booked. Photo by IAN WALTON/POOL/AFP via Getty Images.