The incident took place in central Khartoum on Wednesday as opposition parties and supporters gathered to demonstrate against a recent rise in petrol and sugar prices.
A witness saw riot police snatch a TV camera from an Aljazeera journalist filming the crowd.
The police chased him and beat him with sticks while firing tear gas at those around.
An Aljazeera reporter said that the Sudanese police attacked Ibrahim Muhammad Abdul Rahman, a cameraman for the channel, and snatched his camera while he was covering the protest.
Aljazeera's crew was one of only a few media teams covering the protest due to the security cordon the police imposed on the area in an attempt to prevent the protest, the reporter said.
The reporter said that at least 10 opposition political parties rallied in Khartoum to protest against the economic policies of the Sudanese government.