A modified method of poly (A) RNA purification using oligo(dT)cellulose is described. The purification can be done in tip with cellulose,which consists of only 1/50-1/100 of the usual amount used.Contrast with the typical methods,it not only has the adventages of shorter experimental time and higher proportion of mRNA production, but can also produce mRNA which can be used as template of cDNA synthesis directly.