Police said the victim felt someone nudge him before two men demanded he hand over his phone.
He refused and began backing away before the men attacked him, stabbing him a number of times.
The suspects ran off with the victim’s phone leaving him with serious injuries and bleeding out on the banks of the River Lea.
Police said he is now expected to recover.
The Met’s DC John Kalinzi said: “We know that there were a number of people cycling and walking besides the canal at the time of this incident.
“I am very keen to hear from anyone who has any information but has not yet spoken with police.
“It is vital that we identify these suspects who were ready to inflict potentially fatal injuries to steal a mobile phone.
“If you can help, please don’t hesitate to get in touch.”
Anyone with information should call police on 101 or Tweet @MetCC quoting CAD 6364/05JAN.
To remain 100% anonymous contact the independent charity Crimestoppers on 0800 555 111.