Aegon, an international life insurance and pension company, and Tsinghua Tongfang have jointly invested 300 million yuan ($48.5 million) in Chinese life insurance company Aegon CNOOC amid the nation's booming life insurance market.

Last year, Aegon and Tsinghua Tongfang signed a Joint Venture Agreement to replace Aegon's former partner China National Offshore Oil Corporation in its life insurance company in China, Aegon CNOOC.

"The cooperation is important for us to build our financial business arm by looking into the opportunities in the life insurance market in China," said Lu Zhicheng, Tsinghua Tongfang's Chairman. "This is a great chance to strengthen our financial pipeline."

Alex Wynaendts, CEO of Dutch company Aegon, said that China's life insurance market has a great potential for growth, in the retirement market.

"If you look at the amount of retirement savings in the US and UK, these account for around about 60 to 80 percent of the country's GDP, while the ratio of savings put away for retirement in China's GDP is relatively small, and that leaves much room for growth," he said.

China is the world's fifth-largest life insurance market, accounting for 5 percent of the world's premium volume, and China is expected to have a $190 billion life insurance market by 2018, according to a survey by PwC.

Aegon and Tsinghua Tongfang will each own 50 percent of the life insurance company when the transaction – which is pending regulatory approval - is complete. Tsinghua Tongfang will be the domestic shareholder in the joint venture.