In the perspective of exploring alternative gate dielectrics for the future generation of microelectronic devices, we investigated experimentally and theoretically the interface energy barriers induced on (001) silicon by La{sub 2}Hf{sub 2}O{sub 7}, whose growth has been recently attained by molecular-beam epitaxy. Experimental results show that the 5.6{+-}0.1 eV band gap of La{sub 2}Hf{sub 2}O{sub 7} is aligned to the band gap of silicon with a valence band offset of 2.4{+-}0.1 eV and a conduction band offset of 2.1{+-}0.1 eV. Density functional theory calculations yield valence band offset values ranging between 1.8 and 2.4 eV.