This paper presents a kind of BETA zeolite that was made out of mesoporous material. With MCM-41 mesoporous material being used as silicon source, this BETA zeolite shows improved physical and chemical properties. It not only keeps acidity advantage of microporous zeolite but also inherits some pore structure quality of mesoporous zeolite. Moreover, it also displays very small crystal granule close to the range of nanometer. Owing to these new characteristics, such BETA zeolite provides hydrocracking catalyst with enhanced activity and improved middle distillate selectivity when it is applied in hydrocracking catalyst for treating large molecule heavy hydrocarbon feed oil to produce middle distillates (jet fuel + diesel oil). (c) 2006 Elsevier B.V. All rights reserved.