Abstract: This invention discloses a single-stage process for producing diesel oils of superior quality and low solidifying point from fraction oils under controlled reaction conditions, comprising a hydrorefining step, optionally a hydroupgrading step and a hydrodewaxing step combined in series. The process of the invention is simplified, the operation is simple, the adaptability to feedstocks is good, and the quality of diesel oil product is improved, and when the hydroupgrading step is comprised, the cetane number of the product is further boosted. A hydrorefining catalyst having a higher content of NiO and good anti-coking performance and a hydroupgrading catalyst and hydrodewaxing catalyst having an adequate acidity and strong resistance to NH3 and H2S respectively are preferably used in the present invention to achieve better results.