Can my fiancee obtain a tourist visa to visit me in Australia while her application for a subclass 300 prospective marriage visa is pending?

Technically, yes. Foreign nationals may apply for a tourist visa for entry into Australia while they are in the process of obtaining a subclass 300 prospective marriage visa.

However, in order to qualify for a tourist visa, your fiancee must clearly demonstrate she does not wish to become an immigrant and stay in Australia indefinitely. The Embassy will not approve her application for a visitor visa unless she can establish that she intends to return to her own country after a short visit to Australia in order to complete the fiancee visa process. If the applicant is in a romantic relationship with a prospective spouse from Australia, the Australian Embassy will likely assume that your fiancee intends to marry you in Australia while on a tourist visa, and that you wish to sponsor her to allow her to migrate to Australia and remain in the country permanently. This presumption may be extremely difficult to overcome.

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