While it is well documented that autobiographical memory (ABM) recall is affected in Posttraumatic Stress Disorders (PTSD), less is known about the cognitive mechanisms that underlie this pattern. This paper presents two research studies which investigated the role of thought suppression in the recall of ABMs. Study 1 assessed the role of thought suppression as a correlate of ABM retrieval in an undergraduate student sample (n = 50). The results showed that higher levels of trait thought suppression were significantly correlated with faster recall of negative episodic memories as well as reduced recall of personal semantic memories. Thought suppression remained as a significant predictor of ABM recall, even when the participants’ levels of depression and post-traumatic stress reactions were considered. Study 2 investigated the causal effects of thought suppression on ABM recall. 64 undergraduate students were shown a negative video clip and were asked either to suppress any thought of the video or simply to monitor their thoughts immediately thereafter. Results showed that suppression directly led to significantly enhanced negative episodic ABM recall, as well as a significantly reduced ability to recall personal semantic memories. (C) 2009 Elsevier Ltd. All rights reserved.