However, in late 2013 it said it would cut "diplomatic" ties with Taiwan. A statement from the president's office said the decision was based on national strategic considerations.
Beijing said after learning of the decision that it had not contacted Gambia beforehand.
Wang said on Thursday that the resumption of ties is a natural outcome of previous efforts, follows the trend of the times and is in line with the interests of the two countries and their peoples.
He said both countries will explore cooperation in areas such as agriculture, investment, and trade and infrastructure.
Liu Youfa, former vice-president of the China Institute of International Relations, said the resumption of ties has been "pushed by the interests of both sides".
Liu saw no apparent link between the resumption of ties and Taiwan leader-elect Tsai Ing-wen, of the pro-independence Democratic Progressive Party, taking office on May 20.
The past eight years, during which Ma Ying-jeou has served as the island's leader, have been marked by smooth exchanges between the mainland and Taiwan, with neither side engaged in a tug-of-war for diplomatic recognition.