This investigation examined the relationship between updating in working memory and the effect of irrelevant speech on reading comprehension. In updating tasks, participants can make two types of errors labelled delayed intrusions and immediate intrusions. Delayed intrusions measures people’s ability to suppress active information in working memory, while immediate intrusions measure people’s ability to inhibit information from becoming too active. In our study, a negative relationship between reading comprehension and delayed intrusions was found, and reading comprehension was disrupted by irrelevant speech. This disruption was larger for participants with poor updating ability, specifically for those who made a lot of immediate intrusion errors. The results suggest that people with poor updating ability are not only less able to comprehend what they read, but also more susceptible to the disruptive effects from background speech while reading.