Kasabian Newton-Smith, eight, was diagnosed with cancer at the age of two and has two inoperable brain tumours.
Football teams, players and individuals are being asked to tweet with #1LastSmile4Kasabian.
His father Simon Newton-Smith said: "I just hope he is awake enough to know if he meets Wayne Rooney."
The organisation Grassroots Football said: "We appeal to the entire footballing world to join together and send Kasabian 1 last smile."
People are being encouraged to wear a football strip, hold one finger in the air and smile for a photograph.
Billy Sharp, who plays for Sheffield United, has tweeted a picture using #1LastSmile4Kasabian featuring Manchester United star Wayne Rooney and Liverpool's Adam Lallana.
Kasabian, from Parson Cross, Sheffield, has been diagnosed with Ewing sarcoma and has had 111 radiation treatments.
He has been treated for five other tumours in six years.
He is now confined to bed at home and his family celebrated his ninth birthday, which was to be in December, early.
His mother Kay said the campaign was the idea of some friends who wanted to give her son "one last smile" and meet the England player.
Kasabian had "desperately" wanted to follow in his big brother's footsteps and play football and he had three games for Southy Wolves U10's, his father said.
Watching him play football "was a dream", Mr Newton-Smith said.
Kasabian has seen one Manchester United game at Old Trafford  and "absolutely loved it" his dad said.
The young boy, who has six brothers and sisters,  has previously taken part in fundraising efforts for Sheffield Children's Hospital and cancer charities.
The BBC has contacted Wayne Rooney's management for a comment.
A social media campaign is trying to give a terminally ill boy "one last smile" by getting him to meet footballer Wayne Rooney.