Thirty-four people were identified as refugees, 16 of them from Syria, police from Gries am Brenner told the Austrian Press Agency.
Of the Syrians, eight were children, including a one-year-old baby. The remainder were mainly from African countries, including Eritrea and Gambia.
They were taken off the train at Innsbruck’s main station on Thursday evening and will be sent back to Italy on Friday.
Last weekend 44 refugees, mostly from Syria and Eritrea, were found on the same train route - travelling from Germany.
According to the so-called Dublin II Regulation governing the treatment of refugees, potential asylum seekers must be sent back to the first EU country in which they arrived.
Italy has experienced a record influx of refugees for many months, and has complained that it has repeatedly been let down by its European neighbours, and left to deal with the problem alone.