The Ukrainian striker, formerly of Liverpool, will ply his trade for the Bundesliga new boys in the coming season after failing to impress at the Russian capital outfit
The move marks a return to German football for the striker, having previously played for Borussia Monchengladbach, Mainz, Koln, Bayer Leverkusen and Hertha Berlin.
Voronin signed for Dynamo Moscow in January 2010 from Liverpool in a £4 million deal, but failed to make his mark in the Russian capital, scoring only 17 times in 67 appearances.
The completion of the loan transfer is now pending a medical, according to Fortuna Dusseldorf director Wolf Werner, with neither side confirming whether a buying clause is included in the deal.
The 33-year-old, who has 74 Ukraine caps to his name, made two appearances for his country's national team at Euro 2012.