The Panthers took a 68-64 lead on a pair of free throws by Jerica Coley with 1:41 to go in the game.
FAMU regained the lead as Kimberly Sparkman scored the next five points for the Lady Rattlers as she she made a layup with 48 seconds left, followed by a three-pointer with 21 seconds left in the game, giving FAMU a 69-68 lead.
The Lady Rattlers opened the first half with a 6-4 lead on a made free throw by Keturah Martin.
FIU would tie the game at 6-6, the first of 10 ties in the game on a pair of free throws by Marita Davydova with 15:59 to go in the first.
Then FIU would extend their lead to 16-12 on a three pointer by Zsofia Labady at the 11:56 mark of the half, capping an 8-3 run by the Panthers.
FAMU would regain the lead as they went on a 10-4 run, giving them a 22-20 lead, capped off by Sparkman layup with 8:51 left in the first.
The Lady Rattlers would then close out the half with a 15-8 run as Cristal Lirano scored FAMU's final two points of the half on a pair of free throws with one second left in the game.
FAMU finished the first half shooting 50-percent from the field (14-of-28), while FIU also shot 50-percent (11-of-22).
FIU opened the second half with a 7-0 run as they tied the game at 37-37, capped off by a layup Davydova with 17:29 to go in the game.
The combination of Sparkman and Grice would give the Rattlers a 42-37 lead as Sparkman made a layup at the 17:17, followed by a Grice three-pointer with 16:41 left.
FIU would regain the lead again on a Davydova layup with 13:33 left in the game, giving the Panthers a 45-44 lead.
A pair of field goals by Grice and Martin gave the Lady Rattlers a 50-47 lead with 11:50 left in the contest.
In the final 11 minutes, the lead would change times four times as FIU held on for the 70-69 win.
The Lady Rattlers finished the contest shooting 44.4 percent (28-of-63), while the Panthers shot 47.3 percent (26-of-55). FIU held the rebounding advantage over FAMU, 42-27.
FAMU (3-10) was paced by both Grice and Sparkman as they both combined for 48 points with Sparkman scoring a team-high 28 points, and Grice chipping in 20 points. Martin led the Lady Rattles on the boards with five.
FIU (8-5) had three Panthers to score in double figures as Coley scored a game-high 35 points to lead all scorers, followed by Davydova with a double-double as she scored 11 points and pulled down 11 boards, while Mansare added 10.
The Lady Rattlers will return to action on Monday, Jan 7 as they will host Bethune-Cookman in their first Mid-Eastern Athletic Conference contest of the year in a 7 p.m. tip.