Human rights groups and U.N. experts have accused Nigerian police of killing suspects without justification and torturing those in detention.
Nigeria is also plagued by frequent armed robberies, and motorists complain police roadblocks appear to be more effective at collecting bribes than fighting crime.
Interior Minister Godwin Abbe said Nigerian President Umaru Yar'Adua had asked British Prime Minister Gordon Brown for help at a Commonwealth summit in Uganda that ended on Sunday.
"The British government is ready to support us in reorganising the Nigeria Police Force and empower it to be able to carry out its assigned role of ensuring law and order," Abbe told reporters after a meeting of security chiefs with Yar'Adua.
Abbe said a committee will soon be set up to work on details of an assistance programme from Nigeria's former colonial ruler.
National police chief Mike Okiro said two weeks ago that police had killed 785 suspected armed robbers in three months and lost 62 of their men, prompting campaigners to call for a probe of the extra-judicial killings.
Armed robbers target private homes, public places and vehicles stuck in traffic jams. They often mount roadblocks to rob people on the highways. Police have made little headway in stopping robberies despite their drastic methods.
Officers routinely torture suspects, shooting them in the legs, beating them and hanging them from the ceiling to extract confessions, a U.N. special rapporteur had said in March.