Abstract: A hydrotreatment process for effecting hydrotreatment of a liquid hydrocarbon feedstock containing a mixture of liquid hydrocarbons together with organic sulphurous impurities in which a desulphurised liquid first hydrocarbon fraction is contacted with a first stream of desulphurised recycle gas to produce (A) a vaporous mixture including unreacted hydrogen, hydrogen sulphide, and a second hydrocarbon fraction including relatively more volatile components of the mixture of hydrocarbons and (B) a third liquid hydrocarbon fraction including relatively less volatile components of the mixture of hydrocarbons as well as residual sulphurous impurities, the vaporous mixture and the third liquid hydrocarbon fraction being recovered as separate streams from the contact zone. The third liquid hydrocarbon fraction is contacted with a mixture of make-up hydrogen-containing gas and desulphurised recycle gas to cause hydrodesulphurisation of residual sulphurous impurities in the third liquid hydrocarbon fraction.