Core-shell Li2TiO3-Li4SiO4 has been suggested as an advanced tritium breeder for outstanding mechanical strength and rich lithium. However, no study has reported on the release behavior of hydrogen isotopes from core-shell Li2TiO3-Li4SiO4. This paper focuses on a deuterium exposure experiment to investigate deuterium release behavior. X-ray diffraction, Raman, and electron spin resonance measurements were adopted to analyze the phase change, crystal structure modification, and defects before and after deuterium exposure. Thermal desorption spectroscopy was used to study the deuterium release behavior of core-shell Li2TiO3-Li4SiO4. Deuterium release from single Li4SiO4 and Li2TiO3 was also examined for comparison. The similarity of the deuterium release profiles between core-shell Li2TiO3-Li4SiO4 and Li4SiO4 was observed, which was considered to be caused by the incomplete coverage of shell Li2TiO3 on the core-shell samples.