Blues boss Roberto Martinez says McAleny's temporary switch to the capital - which runs until Monday 6 January, 2014 - is the perfect move at this stage of his career.
Martinez told evertontv: "Conor has been doing really well in pre-season. He's a boy that's got a real talent and a real knack for scoring goals out of nothing and that's something that in football is rare to have.
"For Conor, the next stage is to play some first team football and we've got that opportunity to do it at Brentford, a setup that is very well run and manager that is going to allow Conor to develop.
"We are very happy to be able to allow Conor to go and play his football and to carry on his development in a very controlled environment and in a positive environment."