The Turkey international has been sidelined since the first leg of the Liga leaders' UEFA Champions League quarter-final first-leg draw with Barcelona at the start of this month.
However, the 27-year-old trained with his team-mates on Sunday and could line up against Jose Mourinho's men at Vicente Calderon on Tuesday in the semi-finals of Europe's premier club competition.
Atleti said on their official website: "The first team trained for an hour and a half at the stadium, preparing for the semi-finals first leg against Chelsea.
"(Coach Diego) Simeone could count on all of the players in the team."
Turan has been a key player for Simeone's side and his return should enhance their chances of securing a famous Champions League and La Liga double.
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