Royals manager Brian McDermott moved quickly to bolster his attacking options following the news Jason Roberts is expected to be sidelined for up to a month with a hamstring injury.
England youth international Afobe has previously enjoyed time out on loan with Huddersfield in npower League One, and McDermott was pleased to have landed his man.
He told Reading's official website: "We're delighted to have him, he wanted to come here and that was important because he had other options.
"We know him very well, we have watched him from a very young age. He's played a lot of games for England right up to the Under-19s and then out on loan last season as well.
"He's a good addition to the squad and will help us with eight games to go."