Inverness failed to make it six wins in a row as Falkirk battled to a win in a keenly-contested match.
Gerard Aafjes scored the winner for Falkirk
The home side took the lead when Dutch defender Gerard Aafjes' superb diving header broke the deadlock.
John Rankin passed up a series of chances for the visitors and both sides spurned opportunities as the game opened up in the second half.
The Caley Thistle fans were left to rue their side's lack of a cutting edge as the Bairns held on for the win.
Inverness midfielder John Rankin had the first effort of the match, with a stinging left-footed volley form 25 yards, but Falkirk keeper Tim Krul was equal to the shot.
Falkirk hit back and Moutinho made a great run into the Inverness box, but he had little in the way of support form his teammates and the chance was gone.
Moutinho then turned his man and fired in an effort which flew just past the post.
Rankin again passed uip a decent chance when his shot dipped just over the bar from the edge of the box.
Falkirk youngster Scott Arfield then played in Moutinho who then played the ball across goal to Graham Barrett, but Barrett failed to make the most of the chance.
After a promising start the match turned into a scrappy affair, as both sides struggled to find a way past the opposing defence.
Caley Thistle then created a chance out of nothing as Rankin collected a flick from Marius Niculae, but instead of trying his luck form the edge of the box, he elected to pass and failed to find a team-mate.
Falkirk's Scott Arfield (left) made some driving runs as the Bairns held off Inverness
Falkirk then took the lead as the match sparked into life. Jack Ross's corner came in from the left and Gerard Aafjes' diving header flew into the top corner of the net.
Rankin passed up yet another good chance directly from the restart as he flashed a volley wide of the post from midway inside the box.
Grant Munro tried to get Inverness back into the game with the first chance of the second period, but his audacious overhead kick from close range went straight to Krul.
Falkirk then took hold of the game, and forced a series of corners, but from the last of these, taken by Moutinho, Michael Higdon could only put his header over the bar.
Craig Brewster's substitutions brought Inverness back into the game, but, despite regaining the initiative, the visitors found it hard to break down dogged Falkirk resistance.
Substitute Russell Latapy went close for the Bairns with a low, driven free-kick, but his effort was wide of the mark.
Michael Higdon went close from the resultant corner, but again his header was too high as Falkirk came roaring back into the game.
Fraser then pulled off a terrific save from Moutinho, as the Portuguese hitman went through one-on-one with the keeper, with the Bairns in control as time ran out for Inverness.
Falkirk: Krul, Ross, Scobbie, Aafjes, Holden, Cregg, Arfield (Milne 68), Thomson, Moutinho, Barrett (Latapy 57), Higdon (Finnigan 82). Subs Not Used: Olejnik, Allison, Riera, Mitchell.
Goal: Aafjes 35.
Inverness CT: Fraser, Tokely, McGuire, Munro, Hastings, McBain (Bayne 62), Black, Duncan, Cowie (Wilson 62), Niculae, Rankin. Subs Not Used: Malkowski, McAllister, Proctor, Gillespie, Duff.
Ref: C Thomson