An election to the 56th Parliament of the United Kingdom for the constituency area of Cardiff West, held as part of the general election on 7 May 2015.
Labour hold by Kevin Brennan with a majority of 6,789 - 15.5% - on a turnout of 65.6%.
Candidates
| Name | Party | Vote | Vote share | Vote change |
| BRENNAN, Kevin | Lab | 17,803 | 40.7% | -0.6% |
| TAGHDISSIAN, James | Con | 11,014 | 25.2% | -4.5% |
| MCEVOY, Neil | PC | 6,096 | 13.9% | 6.9% |
| MORRIS, Brian | UKIP | 4,923 | 11.2% | 8.5% |
| AP TOMOS, Cadan | LD | 2,069 | 4.7% | -12.8% |
| BARKER, Ken | Green | 1,704 | 3.9% | 2.1% |
| JONES, Helen | TUSC | 183 | 0.4% | - |
Under section 13(b) of the Representation of the People Act 1985, a candidate gaining 5% or less of the vote share will forfeit their deposit.
An electorate of 66,762, having a valid vote count of 43,792 and an invalid vote count of 113.
Result declared at 06:07 on 8 May 2015.