More than 2,000 of the images involved children, and many were of the most serious kind, Peterborough Crown Court was told.
He was caught when police in Hampshire investigated file-sharing site Limewire and were able to watch the material Drew was looking at.
Drew, formerly from Perry, near St Neots, Cambs, admitted 21 offences of making and possessing indecent images of children.
He was jailed for 16 months by Judge Neil McKittrick, who told him: "You are here because you have downloaded images of children which are pornographic in nature."
Drew was also made the subject of a Sex Offences Prevention Order, banned from being in the presence of a child under 16 without an adult or carer present, banned from taking part in activities with children under 18 without the permission of the chief constable, banned from working with children, and banned from having computers on his premises unless the police were informed and could carry out checks at any time.
Judge McKittrick also ordered the confiscation of Drew’s computers and the images.
Nicholas Cotter, prosecuting, said Drew’s home in Perry was raided in January last year and a large amount of adult pornography was found on his computers and the system also contained 2,013 pornographic images of children aged from six months to 15 years.
Mr Cotter said Drew, who admitted collecting pornography from the age of 18, had put many of the child images in order.
Richard Ferry-Swainson, defending, said: "There is no question that the images contained on his computer were of the worst order."
He said Drew, who had not been in trouble before, had downloaded the images for his own benefit and had not distributed them.
Mr Ferry-Swainson told the court Drew was a hoarder who had worked in the computer industry and who would have been able to remove the images if he had wanted to.
He added that Drew recognised he had a problem, but that "he did not think the images he had been looking at were serious or were breaking the law."
