The 24-year-old will be available for the English county club in all the three formats from April to mid of September but will be missing a couple of County Championship games in June when Australia play England in One-Day International and Twenty20 International series.
Head recently led Adelaide Strikers to their maiden Big Bash League title win and had amassed 374 runs from nine games at an average of 53.42 and a strike-rate of 133. He has also been handy with the ball picking four wickets.
Worcestershire vice-chairman Tim Curtis is delighted with Head's signing and insisted that the club is on the lookout for another overseas player to fill in the gap when he leaves for Australian duty in June.
"We are delighted to have signed Travis," Curtis said.
"Travis will start the season with us in April and will be with us right through to and including T20 finals day on September 15. He will miss two championship games in June when Australia have an ODI Series and a T20I against England over here.
"But he is ambitious to play Test cricket and Cricket Australia have encouraged him and other young players to play cricket this summer."
© Cricket World 2018