No one was reported hurt in the incident and police forced the convoy of around 250 people, which was heading to Gaza in a show of solidarity with the Palestinian residents of the impoverished territory, to turn back to Cairo.
Police also arrested several people who helped to ram the bus into the checkpoint and others who overturned a police car, they said.
Hundreds of policemen were on the streets of Al-Midan, 25 kilometres (15 miles) from El-Arish in the northern Sinai peninsula to prevent the convoy from driving to the Rafah border town, the police said.
Ordinary Egyptians and trade unionists had joined the convoy organised by the Islamist Labour Party, which has been disbanded by the authorities.
Conditions have deteriorated for the 1.5 million Palestinians living in the Gaza Strip since Israel tightened restrictions on the territory after the Islamist Hamas seized control in mid-June.
On Friday Israel's high court ruled that the state could continue with month-long fuel cuts to Gaza, but ordered a delay on plans to reduce electricity supplies too, officials said.
The rulings came in response to a petition by 10 Israeli and Palestinian human rights groups, which had called the moves to limit Gaza energy supplies an act of illegal collective punishment that endangered civilians.
Israel -- which supplies all fuel and majority of electricity to Gaza -- began restricting fuel shipments to the territory on October 28, saying the move was in response to continuing rocket fire.
