The lawyer representing them says Brisbane's Church of Jesus Christ of Latter Days Saints, also known as the Mormon church, is forcing its parishioners to use English during worship.
The Mormon church in Samoa says there is no policy to ban any languages, and only its head office in Salt Lake City has the authority to make policy decisions.
New Zealand based Samoan lawyer Olinda Woodroffe has told Pacific Beat the ban is unfair and unreasonable.
"Suffice to say that the concern of the people in banning them from singing, praying or giving testimony in Samoan language in the Mormon Church or Latter Day Saints in Brisbane is continuing," she said.
"I am somewhat surprised to hear news that they are allowing it...the people I'm representing are still being banned in using their language in the church."
Ms Woodroffe led a group of Samoan Mormons from Brisbane have travelled to Apia to raise their concerns with Prime Minister Tuilaepa Sailele.
"Whoever you are, whatever church, the Samoan language is a very important part of our identity," she said.
"What we said to the prime minister is 'Samoa may be a small country, but the Samoan language is so important to our identity'.
"If we don't all together...fight against any move to ban the Samoan language from use...that is they duty of all Samoans, including the prime minister."
Ms Woodroffe says Mr Tuilaepa promised to write to the Pacific community and the Mormon church in Utah over the issue.
She say the matter has been listed to be heard in the Australian Federal Appeals Court next May.