Erie lake Ontario has the shortest shoreline (712 miles) Lake Erie has the smallest volume (116 miles cubed)
If you are talking about shoreline, none of them. All five Great Lakes have at least some American shoreline.
Lake Erie
Lake Michigan.
The great lake state that has more shoreline than the entire US Atlantic Seaboard is Michigan.
Lake Erie has the shortest retention time of about 2.7 years
Ontario
Lake Superior has more shoreline than the entire eastern seaboard of the United States. With its countless islands and intricate shoreline, it boasts over 2,700 miles of shoreline, which exceeds the approximately 2,100 miles of the eastern seaboard. This vast expanse makes Lake Superior the largest of the Great Lakes by surface area.
The only state that touches four of the five great lakes is Michigan. Michigan has shoreline on Lakes Superior, Michigan, Huron and Erie, but not on Lake Ontario. New York has shoreline on Lakes Ontario and Erie. Pennsylvania and Ohio have shoreline on Lake Erie. Indiana, Illinois and Wisconsin have shoreline on Lake Michigan. Minnesota and Wisconsin have shoreline on Lake Superior.
Michigan has approximately 3,200 miles of shoreline with beaches. Michigan's shoreline is made from the Great Lakes which is a freshwater lake.
Pennsylvania has a shoreline on Lake Erie. Oklahoma does not.
Leech Lake has 314 miles of shoreline using the outline of the lake (per DNR). If you include the shoreline of the many islands, the Leech Lake Association says the lake is over 600 miles.