Calvin Grieves had £15 stolen from him and was violently pushed to the floor by his attacker in Eastwood Cemetery.
His mum Rachel Boyd said she was “absolutely disgusted” someone could attack a child.
She said: “I can’t believe it to be honest.
“I feel guilty for letting him go and I feel absolutely disgusted that someone could attack a child.
“I’ve never heard of anything like it.
“I just hope they catch him before he does it to anybody else.”
Calvin had walked just a few minutes from his home in South Street to the Premier Shop in Main Street.
As he was walking home through the cemetery, he was robbed.
Rachel said: “A man snatched the money out of his hand which the shopkeeper had put into a sandwich bag for him, then pushed him to the floor and swore at him.
“He then grabbed the bag with the cans of pop in and stamped on some of them before he ran off.”
Calvin, a pupil at Brookhill Leys Primary School, was left with cuts on his wrists and knees and bruises on his elbow.
Rachel went to the cemetery immediately after the attack and said she found the burst cans of drink and 57p in loose change which the robber had discarded after taking the £5 and £10 notes.
The robber had been stood outside the Premier Store as Calvin had arrived, but was not there as he left.
Rachel, aged 34, has suffered criticism on social media for allowing her child to go the shop on his own, and said she felt very guilty.
She said Calvin was unusually independent and had nagged her for months to let him go to the shop on his own.
She said: “He’s not like a normal seven year old. He’s so sensible,.
“He had begged me and begged me to go to the shop for a long time, so I let him go. I walked him to the end of Church Street and watched him go.
“Then five minutes later he came running up screaming and saying a man had attacked him.”
The mum-of-two said she used to let Calvin go to the shop on his own where they used to live, because it was just at the end of their road.
However, since moving to South Street six months ago, she had not let him go until now.
She said: “He loves his independence.
“I leave him at the school gates to just walk into school on his own because he really likes that bit of independence.”
The robbery happened on Saturday, October 17, at about 1.40pm.
The robber has been described as tall with brown hair and wearing a black woolly hat, white T-shirt and blue jeans.
Anyone with information about the incident is asked to call Nottinghamshire Police on 101.
Pictured - Calvin and his mum Rachel Boyd.