Benthic organisms that inhabit stream sediments live in an inherently unstable physical environment, making them susceptible to injury from sediment movements, especially during periods of high flow. Stream flooding is common and is increasing in severity and frequency due to climate change, exacerbating the injury risk to infaunal organisms. Annelids are abundant in stream sediments and their soft, elongated bodies should make them particularly susceptible to injury from shearing and crushing forces of moving sediments. However, such injuries have not previously been studied. We performed laboratory experiments to investigate how sediment size and sediment movement speeds affect injury in two common freshwater annelid species, the tiny naidid Pristina leidyi and the large lumbriculid Lumbriculus variegatus. We simulated natural sediment mobility by swirling annelids with natural substrates of five size classes at five speeds, and also assessed the recovery of P. leidyi following a range of damage severity. Our results indicate that sediment mobility can cause substantial injury to both small and large bodied annelids. The small-bodied P. leidy experienced the greatest damage with small to intermediate sediment sizes (fine and medium gravel), while the large-bodied L. variegatus experienced the greatest damage with intermediate to large sediment sizes (medium and large gravel). Both species experienced greater injury with increased sediment movement speeds. Pristina leidyi exhibited a high capacity to recover from sediment mobility damage, with recovery time and death increasing with injury severity. Our findings suggest that injury from sediment mobility may be ecologically important in soft-bodied stream infauna.