The Germany midfielder has not featured for club or country since August 2013 - therefore missing his nation's World Cup triumph - due to an ongoing back problem.
However, Gundogan has now declared himself ready to return at the RheinEnergie Stadion on Saturday.
Gundogan resumed light training during the close-season and has been stepping up his workload since then, playing 45 minutes in a behind-closed-doors friendly last Friday.
"I am now available," he told Sky Sports Deutschland. "The plan is that I, as soon as the national players coming back, am again fully integrated into the team.
"I am assuming that I am, on the weekend against FC Cologne, in the squad."
Dortmund - who have endured a mixed start to the season, winning just one of their last five matches in all competitions - could also have Marco Reus (ankle) back for the Cologne game after he featured alongside Gundogan in last week's friendly.
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