Midfielder Filip Kiss has returned to Ross County on a season-long loan from Cardiff City.
The 23-year-old Slovakian scored six goals in 17 goals for the Staggies last season, having arrived at Victoria Park in January.
Also joining up is 25-year-old left-back Uros Celcer, with the Slovenian having left Parma without making an appearance for the Serie A club.
Teenage midfielder Rosario Latouchent arrives from France.
County manager Derek Adams has been busy reshaping his squad after last season's seventh place finish in the Premiership and the latest additions take the number of new arrivals up to 11.
"We have good competition for places now," Adams told BBC Scotland.
"It's been a good summer and we have a strong squad that we are happy with.
"We've been making big changes every year for the last seven years now. It's just the nature of how we do our business."
Kiss was an instant success in the Highlands, scoring four goals in his first two games, and Adams is delighted to have him back.
"Filip was a very good player for us last season," he added. "He gave us goals from midfield, he gave us creativity and a bit of steel.
"He's a talented boy and he was able to get his first international cap last season while playing for Ross County."