Jurgen Klopp’s men have suffered a dramatic fall from grace this season and head to the international break in the relegation places.
Attacking midfielder Kampl has been lined up to provide some much-needed impetus, with the 24-year-old moving from Red Bull Salzburg.
He has signed a contract through to the summer of 2019, with the 14-cap international moving for an undisclosed fee.
“Kevin Kampl is a versatile attacking-midfielder, who we have been observing for some time. His style of play fits in perfectly with our own,” said Borussia Dortmund sporting director Michael Zorc on the club’s official website.