BEIJING — He is known in China as the “godfather of real estate,” helping lay the groundwork for private homeownership in China, a move that enriched millions and laid the foundations for a vibrant and thriving Chinese middle class.

Now, Meng Xiaosu wants a lot of Chinese — the older ones, specifically — to cash out.

Older people need to mortgage their homes to address China’s looming demographic bust, Mr. Meng argues. Because of China’s now-defunct one-child policy and other social trends, the country has a rapidly graying population that someday soon may become too expensive for the Chinese government to support.

Mr. Meng's proposed solution is to bring reverse mortgages to China. Called a house-for-pension plan in China, a reverse mortgage allows homeowners to tap the equity in their homes by taking out loans against it.

His argument faces deep business and cultural opposition — mortgaging homes is a tough sell in a country where parents traditionally passed them on to their children — and only a few dozen people in all the country have signed up so far. But he argues that China may have little choice.