The public is being asked to help find Mabindra Pun and Saurab Pun, both aged 14, after they went missing earlier this week.
Mabindra was last seen leaving a property on Rawson Place, Haymarket, in the city centre at about 12pm on Sunday.
He is described as being of Indian Sub-Continental appearance, about 140cm tall, thin build, with black hair and brown eyes.
Mabindra was last seen wearing a navy shirt and black pants, with black and white sneakers.
Saurab was last seen at Sydney International Airport, at about 6.30pm yesterday.
He is of Indian Sub-Continental appearance, about 155cm tall, thin build, with black hair and brown eyes.
Saurab was last seen wearing a black T-shirt and shorts, with black and grey shoes.
Anyone with information about the two boys should contact South Sydney police or Sydney City police. They can also call Crime Stoppers on 1800 333 000.