The purpose of the present study was twofold. First, to examine the psychometric properties of the Penn State Worry Questionnaire (PSWQ) and the Metacognitions Questionnaire-30 (MCQ-30) in a Turkish sample. Second, to investigate metacognitive predictors of pathological worry and obsessive-compulsive (o-c) symptoms in this group. The sample included 561 non-clinical participants. Consistent with non-English versions, the Turkish version of the PSWQ was found to have a two-factor structure. The MCQ-30 was shown to be composed of five factors similar to the English version. Reliability analyses indicated that both the PSWQ and MCQ-30 possessed high internal consistency, split-half reliability and test-retest coefficients. As expected, both scales positively correlated with measures of o-c symptoms, trait anxiety, and anxiety and depression, as well as with each other. Negative and positive metacognitive beliefs about worry were significant predictors of both pathological worry and o-c symptoms. Cognitive confidence emerged as a specific predictor of worry, while beliefs about the need to control thoughts emerged as a unique predictor of o-c symptoms. Copyright (C) 2008 John Wiley & Sons, Ltd.