The great barracuda (Sphyraena barracuda) is a solitary predator that inhabits tropical and subtropical regions of the Atlantic, Pacific and Indian oceans. Adults can reach over 2 m in length. . Sphyraena barracuda is well-known as a voracious and fast predator among coral reefs and sea grasses around the world. Its diet is diverse, based on mid- water-dwelling fishes and cephalopods species (Porter and Motta, 2004).  Its foraging strategy consists of lie and wait until the prey is visualized.  After this, by ram feeding behavior, the capture of the prey is reached by dramatically accelerated swimming.  Several aspects made this species unique among fishes, but probably one of most significant is related to the effective cutting force of their teeth.  While the kinematics of the strike in this species has been studied by Porter and Motta (2004), there is still no study of the morphology of the jaw and the force applied to prey during prey capture. In this study we investigated bite force and functional morphology of the feeding mechanism of the great barracuda Sphyraena barracuda through ontogeny. Theoretical estimates of bite force at two bite points were calculated for a size series of barracuda ranging from 18 to 130 cm TL (n = 27) using a three dimensional static equilibrium model. In addition, electromyography was used to determine the role of adductor mandibulae subdivisions (A1, A2, A3) in jaw closure. All recorded subdivisions were active during jaw adduction, although onset times and activity durations differed among them.  Bite force ranged from 1 – 93 N at the most anterior bite point, and from 3 – 258 N at the most posterior bite point. Mechanical advantage, in lever and posterior out lever, as well as the cross sectional area of the majority of the adductor mandibulae subdivisions scaled with isometry; consequently bite force at both bite points also scaled with isometry. Bite force in S. barracuda increased in proportion to total length during ontogeny, which may be associated with a piscivorous diet throughout its life. When compared to other fishes, values of bite force in S.barracuda are among the lowest relative to its size.