Both sides had already secured their places in the top six ahead of the split and, having already fought out a pair of draws this season, they proved well-matched again.
Mehdi Abeid was a lively presence for St Johnstone in a relatively quiet first half and he had the first chance, dribbling to the edge of the area before firing wide of the target.
The hosts then began to press forward and Andrew Shinnie headed a decent opportunity over the bar from an Aaron Doran cross, while Owain Tudur Jones drew a fine diving save from Alan Mannus.
But clear-cut chances were quite scarce in the opening 45 minutes, although Abeid went close again just before the break with a thumping effort which was not far wide of the target.
St Johnstone were in the ascendancy at the start of the second half and Chris Millar's low shot almost crept past Antonio Reguero, only for the goalkeeper to stick out his hand at the last moment.
However, Inverness then went close twice in as many minutes, firstly when St Johnston goalkeeper Mannus did well to keep out a long-range effort from Tudur Jones which had deflected off defender Frazer Wright, Graeme Shinnie shooting over when the ball came back into the box.
Doran then latched onto a through-ball and was one-on-one with Mannus but the 'keeper was quickly off his line and managed to smother the shot.
Andrew Shinnie was next to try his luck for the hosts and he unleashed a real rocket from the edge of the box which flew just wide.
St Johnstone then enjoyed a brief period of pressure and Liam Craig sent over a fine low cross which Steve MacLean almost got on the end of.
But it was the hosts who came closest to scoring a late winner, Ross Draper getting on the end of a long ball into the box and heading powerfully towards goal, only for Mannus to pull off a fine reflex save and preserve a point which took St Johnston up to fourth.