Exports dropped 12.1% by value last month from a year earlier to $35.75 billion, the lowest in 20 months, the Ministry of Finance said on Saturday.
That followed a 13.1% drop in November, and was slightly better than Reuters poll forecast for a 13.3% contraction.
Taiwan's total exports of electronics components in December fell 1.4% to $16.04 billion, with semiconductor exports up 0.8% from a year earlier.
At $14.28 billion in December, Taiwan's exports to China, the island's largest trading partner, were down 16.4% from a year ago, after suffering a 20.9% drop in November.
December's exports to the United States were down 2.6%, compared with an 11.3% contraction recorded the previous month.