While it is generally acknowledged that metalinguistic awareness plays a role in decoding ability (National Institute of Child Health and Human Development, 2000), less is known about the role metalinguistic awareness plays in comprehension. In the present study, structural riddles and ambiguous sentences differing in the source of linguistic ambiguity were used to study the importance of metalinguistic awareness in reading comprehension. One hundred sixth and seventh graders were tested on 25 structural riddles and 40 ambiguous sentences. Performance was correlated with scores on the reading comprehension and vocabulary subtests of the GMRT4 (MacGinitie, MacGinitie, Maria, & Dreyer, 2000). It was found that both tasks correlated significantly with reading comprehension and vocabulary. A multiple hierarchical regression found that riddle solving explained unique variance in the reading comprehension scores, after vocabulary was statistically controlled. This is interpreted as evidence that metalinguistic awareness is an ability separate from general linguistic intelligence, which contributes to reading comprehension. The implications for instruction are discussed. (Contains 4 tables.)