Former UBS Group AG economist Jonathan Anderson once called it "the most important sector in the universe.”

More than a decade on, Chinese property is again grabbing the attention of global investors — this time for all the wrong reasons.

Mounting signs of stress this week in an industry that accounts for about a quarter of the world’s second-largest economy have roiled China’s credit markets, dragged down the nation’s bank stocks and pummeled commodities from iron ore to copper.