The inspirational lock missed all of the last international season after being injured in a Super Rugby match in May last year and his return will be a major boost for the Wallabies ahead of the arrival of the British and Irish Lions in June.
"I'm a terrible spectator at the best of times, so it's a huge relief to be out of team rehab and in a position to play once again," Horwill said in a Reds news release.
"We've been extremely diligent in not rushing the rehab process to ensure that my hamstring would be ready for when the Super Rugby season kicked off. It's exciting to now be at that stage and I'm just looking forward to Friday night."
Horwill's recovery is good news for the 2011 Super Rugby champion Reds, who kick off their 2013 campaign against the ACT Brumbies in Canberra on Feb. 16.
Reds scrumhalf Will Genia, arguably a more influential figure for the Wallabies than Horwill, is still undergoing rehabilitation after knee reconstruction and is likely to miss the first few rounds of the Super Rugby campaign.