Introduction: Although the number of homeless people in France increased by 50% between 2001 and 2012, few descriptive studies had been conducted on mortality within this population. Studies from English-speaking countries show that homelessness is associated with a high risk of premature death. The objective of this study was to estimate the number of deaths among homeless people in France between 2008 and 2010. Method: The capture-recapture method was used to estimate the number of deaths among homeless people in France using two independent data sources. The first source was the database of the Collectif Les morts de la rue, and the second was extracted from the national database of medical causes of death maintained by CépiDc-Inserm. The sources were matched using an algorithm based on various combinations of variables common to both sources. Results: The number of deaths among homeless people in France between 2008 and 2010 was estimated at 6,730 (95% CI: [4,381–9,079]). The completeness of each source, taken separately, is less than 20%. Conclusion: In the absence of a comprehensive registry of deaths among homeless people, this method made it possible to estimate the order of magnitude of mortality within this population. This method, which is reproducible and was applied to two routinely produced databases, could be used to monitor trends in mortality within this population.