Kristian Brymora has agreed a short-term deal after impressing Lions academy staff.
The centre-forward will come under the tutelage of academy boss Kevin Nugent, who was delighted when the 18-year-old put pen to paper this week.
"I am really happy for Kristian," he told millwallfc.co.uk
"He has been brave and taken a risk to come over to London and earn a contract. He has proved that he's willing to work hard and make it work at Millwall.
"Kristian is a strong centre-forward and he will add some energy to the group. We watched him during an intra-club friendly match and he proved that he has potential.
"I have no doubt he can be successful here if he works hard."
