The boys, both aged 16, were reportedly robbed of their phones after being threatened by the men armed with knives on February 19.
They were on the 229 bus in Bexley High Street at 4.15pm at the time of the reported robbery.
The Metropolitan Police have released an appeal over two months after, showing the faces of two men who officers would like to identify and speak to.
Both men are pictured wearing black hoodies, one going up the stairs of the double decker bus and another outside the bus.
Anyone with information is asked to call police on 101, quoting reference 4889/19Feb.
