The Swede reported the sighting close to midnight on Thursday.
While driving around Söderleden, she said she saw the bear walking down into a ditch.
Police did not react immediately, waiting to hear more reports before sending out a patrol car.
"Even though she says she is absolutely sure, we'll just keep an eye on the situation and see if anyone else reports the same thing," Ulf Lörstad of the local police told the TT news agency.
"Or maybe we'll wait and see if a circus calls to say they've lost a bear."
Bears are much more commonly found in central and northern Sweden. They rarely stray further south than Dalarna.