China regards self-ruled Taiwan as a breakaway province to be united with the mainland eventually.
Last year, Taiwanese suspected of telecom fraud were deported, sometimes forcibly, according to the Taiwanese government, from countries including Kenya, Cambodia and Armenia, to China.
Asked about the Spanish case, An Fengshan, a spokesman for China`s Taiwan Affairs Office, told a regular news conference the decision was taken in part because both the victims and evidence relating to the fraud were in China.
"This course of action has received widespread approval from people from both sides of the Taiwan Strait and the international community," he said.
The Spanish government said on Friday it had approved the extradition of 269 "Chinese citizens" as part of a year-long investigation into an Internet fraud ring operated from several Spanish cities, including Madrid and Barcelona.
Around 839 people were victims and the sum involved in the scam was estimated at around 120 million yuan ($17.5 million), the Spanish justice ministry said in a statement.
Taiwan`s Foreign Ministry said around 200 of the suspects were Taiwanese and that it deeply regretted the decision.
Defeated Nationalist forces fled to Taiwan at the end of a civil war with the Communists in 1949 and China has never renounced the use of force to bring Taiwan under its control.
China has increasingly squeezed Taiwan`s international space since last year`s election of Taiwan President Tsai Ing-wen, of the independence-leaning Democratic Progressive Party.