Hertbertsmithite ZnCu3(OH)6Cl2 is a model S =1/2 kagome antiferromagnet, received much attention last years. From recent studies a sign of a nearby quantum phase transition (QPT) was revealed in this system. Ideal way to induce a QPT is application of high external pressure, which allows to vary the exchange interactions in a system via controlled reduction of distance between magnetic atoms. Presently quantum phase transitions are mostly studied in ACuCl3 spin-dimer compounds, in a relatively small pressure range P < 2 GPa. Hertbertsmithite is a natural candidate to extend the search for a pressure-induced QPT phenomenon. In order to study the QPT phenomenon in this a near-ideal S = 1/2 kagome antiferromagnet, we propose to perform neutron diffraction measurements on deuterated herbertsmithite, with the GEM diffractometer using a sapphire anvil cell in the pressure range up to 5 GPa.