[Display omitted] • Pt@TiO2 was successfully prepared using Pt@MIL-125 as template. • Pt NPs were highly separated inside TiO2 rather than aggregated on the surface. • Photocatalytic H2 production activity for Pt@TiO2 was 6.4 times of it for Pt/TiO2. • The stability of Pt@TiO2 can main at ~ 98% after 5 cycles reactions. • Pt@TiO2 can provide more active sites and facilitate the charge utilization. Pt/TiO 2 , with traditional surface-loaded cocatalyst Pt, not only suffers from Pt aggregation, but also the problem of cocatalyst losing during photocatalytic reactions. Here, porous TiO 2 with embedded Pt (Pt@TiO 2) was successfully prepared via in situ hydrothermal reaction followed by calcination using Pt@MIL-125 as precursor. The characterizations showed that Pt nanoparticles (NPs) were highly isolated inside of TiO 2. The porous structure of TiO 2 can provide abundant pathways for the mass transfer. Photocatalytic hydrogen production reactions showed that Pt@TiO 2 reached to an activity of 4.389 mmol/h/g with the apparent quantum efficiency of 39% at 380 nm, which was 6.4 times that for Pt/TiO 2. Besides, Pt@TiO 2 could efficiently prevent Pt NPs from losing and exhibited a good stability compared with Pt/TiO 2. Dynamic characterizations indicated that the embedded Pt@TiO 2 not only provides more active sites of Pt, but also facilitate the charge utilization, which contribute to the excellent photocatalytic activity. [ABSTRACT FROM AUTHOR]