Feng Yali, 45, who lives close to his restaurant, said she came to the restaurant every day to have lunch after seeing the online post.
"I am not rich either, but I really hope he can collect the money for his medical fees as soon as possible," she said.
Customers have crowded the small restaurant, and an extra six tables have had to be provided outside on the sidewalk.
Jing Xiaomin, Li's wife, said that he has been in the hospital for days, and she has been helping to run the restaurant with her aunt and many others who have volunteered to wash dishes, clear tables and serve the customers.
The wall of the restaurant has been filled with handwritten goodwill messages encouraging the family to be strong.
"If there is love, there is future," said one.
Guo Mei, Jing's aunt, said many people have insisted on giving 100 or even 500 yuan for a bowl of noodles.
"I have tried to give them change, but they refuse and leave the restaurant immediately," she said.
Miao Guojun, the general manager of a company based in Luoyang, Henan province, has asked his employee in Zhengzhou to take his donation of 1,000 yuan to the restaurant, Guo added.
Many others simply leave money at the counter without giving their names.
Some companies nearby have arranged for their employees to eat together at the restaurant at lunchtime, Guo said.
Li said by Thursday he had raised about 30,000 yuan, but it's still not enough for his surgery.
"I never expected so many people would come to eat in my restaurant. I thank all of these kindhearted people," he said.
"I must be strong so that all those who have helped me are not disappointed," he added.
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