The 26-year-old admitted he was guilty of lifting Sharks loose forward Marcell Coetzee and failing to return him to the ground safely in the Reds' 27-22 defeat in Durban on Saturday.
Ioane was a key figure in Reds' run to their first Super Rugby title last season, scoring five tries including in the victory over the Crusaders in the final.
An uncompromising defender, he was one of Australia's most productive tacklers in their Tri-Nations triumph and run to the semi-finals of the World Cup last year.
SANZAR judicial officer Mike Heron said previous disciplinary matters relating to dangerous tackles in 2008 had counted against the New Zealand-born back.
Spear or tip tackling, where a player lifts an opponent into the air and returns them to the ground head first, is outlawed because of the potential for head injuries.
Ioane will miss matches against the Bulls, Force, Brumbies and Stormers before being available again when the Reds travel to Auckland to face the Blues on April 27.