Tiatia, the brother of former All Black and Hurricanes back rower Filo, has been charged with dangerously tackling an opponent – his former Quins team-mate, centre Nick Greenstock – in the second half of the Zurich Premiership fixture against the Exiles.
Tiatia has been asked to appear before a Rugby Football Union (RFU) disciplinary panel at Twickenham on Monday, October 6 (17.00 BST).
Quins currently top the Zurich Premiership table, having opened their season with a comfortable 43-15 win over newly-promoted Rotherham, but the loss of Tiatia, who can play in the front and back rows, would be a blow.