The crush was reportedly triggered after a woman stopped to take a picture of herself at the start of her race.
Organizers ruled out a complete ban on mobile phones as impractical, but said they were using Facebook, television and radio to promote the anti-selfie message in the run-up to the next event on February 16.
"It is almost impossible to ban competitors from bringing their mobile phones," William Ko, chairman of the marathon organizing committee, told AFP on Tuesday.
"What we've been trying to do is to get the message across to take care of yourself and to take care of other runners.
"For the race itself we will have officials to hold some message boards to remind people not to take photos at the start, on the route or at the finish because it is dangerous."
The annual marathon event, which started 18 years ago and is sponsored by Standard Chartered bank, includes half-marathon and 10-kilometer competitions as well as the full 42.2 km marathon distance.
The pile-up in February 2013 happened at the start of the 10-kilometer race after a woman competitor dropped her phone as she was trying to take the snap, according to local media.
As she bent to pick it up runners behind her tripped over her, the South China Morning Post (SCMP) reported at the time, including Hong Kong triathlete Joyce Cheung Ting-yan, who went on to win the women's 10k despite her fall.
Standard Chartered chief executive Benjamin Hung Pi-cheng has called on organizers to stop competitors taking photos of themselves to avoid carnage at the next event.
"The problem was that a number of runners were trying to take self-portrait pictures using their smartphones. What we are trying to do is to encourage people not to do that," the SCMP quoted Hung as saying.
Arrangements for February's races were announced Monday, with organizers saying the total enrollment quota would be 73,000 — 1,000 more than in 2013.