The immigration system includes a travel document insertion port for accepting a travel document retaining individual information which specifies a bearer, a reader for reading individual information from the travel document inserted into the insertion port by a bearer, an acquiring portion for acquiring the bearer's biological information, and a collator for collating the individual information acquired by the acquiring portion with the individual information read from the bearer's travel document by the reader. Further, the system includes an examination portion for examining the passing of a bearer for approval or disapproval based on the result of collation in the collator, a passing ticket issuer for issuing a passing ticket to the bearer who is approved to pass, and a gate for approving the passing of a traveler by accepting the inserted passing ticket issued from the passing ticket issuer.