The child was taken to hospital after he was stabbed in the leg in Ribbleton Lane at around 8.30pm on Saturday (December 4).
Detectives described the stabbing as a "shocking attack" and say they believe the youngster had been "targeted", though they have not said whether it is gang-related.
Lancashire Police said the boy remains in hospital, but his injuries "do not appear to be life-threatening".
The force confirmed that no arrests have been made, but said "inquiries are very much underway" and there is not believed to be a wider threat to the public.
A description of the suspect(s) has not been provided at this stage, but the Post has approached Lancashire Police for further details.
Det Ch Insp Mike Gladwin, of Preston Police, said: "Our inquiries are very much underway and we would ask anybody with information about it to get in touch with us as soon as possible.
"At this time we believe it was a targeted attack and there is no wider threat to the public, however patrols will be stepped up in the area to offer reassurance to residents."
Anybody with information can contact police on 101, quoting log 289 of December 4.
Detectives are also appealing to the public to help find a 29-year-old man wanted after another stabbing in Preston on Wednesday, December 1.
Police want to speak to Ryan George Evans in connection with the stabbing, and say he has links to the Ingol, Ashton and city centre areas
You can find more info on the police appeal here.
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