The 25-year-old, who joined Suning from Serbian side Crvena Zvezda during the January transfer window, had to wait for several weeks before making his bow due to injury.
Yiadom replaced Lingfeng Zhang by the 57th minute, fetching his side’s opener from the spot by the 75th minute.
Brazilian international Alex Teixeira later made it 2-0 when he finished off an assist from Tian Yinong.
Jonathan Aparecido da Silva pulled one back for the visitors with nine minutes remaining, as they pushed for the equaliser, but Jiangsu Suning held on to pick their first victory in three games.
Yiadom's side have now moved up to eighth position with six points, while TEDA, who have Ghana midfielder Frank Acheampong in their setup, have dropped to seventh with four points.
Yiadom is expected to make his debut start when Suning travel to face Guangzhou R&F on Friday.