Ex-navy lieutenant Chien Ching-kuo was convicted of violating the national security law along with Lu Chun-chun.
Lu recruited Chien to join the Chinese Communist Party with a paid overseas trip and cash gifts in 2009, said the Kaohsiung district court in southern Taiwan.
According to the court, the pair had arranged for several officers to go on overseas tours paid by Chinese officials in a bid to recruit them to spy for Beijing.
This included a former commander in charge of political warfare at the navy's meteorology and oceanography office, who agreed to collaborate.
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Lu's sentence was suspended for three years on the ground that he has no prior criminal record, the court said.
In a separate trial, Chien was sentenced to three years in prison last year for leaking confidential military information to China, including some of Taiwan's warship deployments and missions.
Taiwan has been hit by a string of spy scandals in recent years.
Last month, the supreme court sentenced a former air force lieutenant colonel to life in prison for spying for China.
Intelligence gathering has continued despite warming ties with China under the island's current Beijing-friendly government.
Taiwan and China have spied on each other ever since they split in 1949 at the end of a civil war.
Beijing still regards the island as part of its territory awaiting reunification, by force if necessary.