Fields succeeded Karen Rolton as Australia captain last year
Alex Blackwell was named Australia's captain for the ICC World Twenty20 in the West Indies after incumbent Jodie Fields withdrew because of injury.
Fields, 25, aggravated a hamstring injury originally sustained in January and will undergo surgery on Saturday.
New South Wales wicketkeeper Alyssa Healy, 20, has been named as Fields's replacement in the Caribbean.
"I'll go through rehabilitation and look forward to be back playing again this summer," said Fields.
The Queenslander took over from Karen Rolton as skipper following Australia's defeat to England in the final of last year's World Twenty20 at Lord's.