It is also threat to peace, stability, safety and maritime security in the South China Sea, it added.
"Once again, Vietnam resolutely opposes Taiwan's actions and demand that it ceases similar activities in the future," Foreign Ministry deputy spokeswoman Nguyen Phuong Tra said at a regular press conference.
A Taiwan News report said Wednesday that Taiwan's drill on the Ba Binh Island, known internationally as the Itu Aba Island, would last from Wednesday to Friday. The drills will be held from 6 a.m. to 9 p.m. on Wednesday and Thursday, and reviewed on Friday, the report said.
Defense officials from Taiwan were also present on the island to oversee the drills.
Taiwan’s Ministry of Foreign Affairs had notified Vietnam of the drills, the Taiwan News report said.
Last month, Foreign Ministry spokeswoman Le Thi Thu Hang already denounced Taiwan's planned live-fire drills on Ba Binh Island in November as a serious violation of Vietnam's sovereignty.
She said the ministry was closely following the situation and developments in the East Sea, using the Vietnamese name for the waterway.
Taiwan's repeated drills around Ba Binh Island threaten peace, stability, maritime safety and security, create tension and complicates the situation in the waters, she added.
Ba Binh is the largest naturally occurring island in the Truong Sa (Spratly) Archipelago, which Vietnam asserts its sovereignty over.
Vietnam has repeatedly said it has full legal grounds and historical evidence for its indisputable sovereignty over the Spratly and Paracel archipelagoes in accordance with international law.