Li's field (Chinese: 李氏力場) is a tongue-in-cheek conspiracy theory in Hong Kong over the existence of a force field that repels tropical cyclones from the city.

The "Li" in Li's field refers to local business tycoon Li Ka-shing, the implied developer of the field. The basis of Li's field rests on the way Hong Kong's government is organized. The city's Commerce and Economic Development Bureau oversees the Hong Kong Observatory,^[1] and that has led to speculations the Observatory bases its issuance of tropical cyclone warning signals on economic reasoning, instead of scientific reasoning.

In Hong Kong, schools above kindergarten level are shut down when Tropical Cyclone Signal Number 8 is issued (kindergarten classes are suspended when Signal Number 3 is issued),^[2] and all non-essential staff at a workplace are sent home.^[3] Some believe businesses have pressured the Observatory into avoiding the issuance of Typhoon Signal Number 8, in an effort to avoid economic losses.

In response, former Observatory Chief Lee Boon Ying told reporters in 2010 the Observatory has always put the safety of Hong Kong residents as its first priority, and is not swayed by business or economic concerns.^[4]

From 2005 to 2006,^[5] and again in 2010,^[6] the Observatory did not issue a single tropical cyclone warning above Number 3.^[7]

Media reports in 2010, citing research by the Observatory, revealed the reason behind the fewer occurrences of Signal Number 8. It is believed that an ocean temperature difference between the South China Sea and the Pacific Ocean provides the explanation.^[11]

Li's force field has been mentioned in local cultural media, and has been the subject of many Internet memes.^[12]

• Bielefeld conspiracy
• Birds Aren't Real
• Hong Kong tropical cyclone warning signals
• Li Ka-shing