The Australian Telegraph reports that the victim was attacked by a scooter rider who was making the school run to pick up her child from a primary school in Meilan District, Haikou City.
According to eyewitnesses, the 42-year-old told the unidentified woman that she was not permitted to park her vehicle in front of his store.
Following a "violent fist fight", the woman made a lunge at the man's crotch, leading to his collapse and death.
Dr Irwin Goldstein told TNT magazine that the shopkeeper may well have suffered cardiac arrest.
Goldstein explained: "The testicles are exquisitely sensitive to touch and there is a huge release of adrenalin when there is excessive force applied to these organs.
"Testicular pain is referred to the lower abdomen, mesenteric plexus, and causes men to stop abruptly what they are doing, lie on the ground, close their eyes and bend their knees."
The specialist added: "A heart attack could certainly result from severe testicular pain from squeezing."
> Shocked woman dies at own funeral
> Read more unusual stories here