Beds Police are appealing for witnesses following the stabbing on Bradgers Hill Road on Monday, May 23 at around 2.50pm.
It is reported that a large group of males were gathered outside the college at the time of the assault.
The 18-year-old victim obtained minor injuries and is receiving treatment for lacerations to his arms and shoulder in hospital.
Temporary Detective Sergeant Chris Smith said: “We are appealing to anybody who witnessed the incident or any events leading up to the incident to get in touch with us.
“Any information you have could help us establish the circumstances surrounding this incident.
“Knife crime will not be tolerated in our communities and we will leave no stone unturned in bringing perpetrators to justice.”
Call 101 or report online quoting, 53 of Monday, 23 May.
Crimestoppers can also be contacted anonymously on 0800 555 111.
In a statement shared on social media, Luton Sixth Form College said it was unable to make further comments at this stage as the incident is part of an ongoing investigation.
However, it added: "We want to reassure the public that we are working very closely with the police to support them with their enquiries and will be increasing our presence and security in and around the college. We would urge anyone who has any information about this serious matter to get in touch with the police immediately by calling 101."
Altaf Hussain, Principal and CEO, said: "Whilst this incident did not happen on our campus, as it was near to the college it will inevitably heighten anxiety for the public and as such we are likely to see an increased police presence while the investigation continues.
"We know at this stage some students and families may be particularly affected and they are beign supported by our counselling teams.
"Knife violence impacts all our communities and this is our time to come together to ensure we tackle this problem in a thoughtful and meaningful way so we can continue to keep each other safe."