The four-day 'bed-net blitz' will give people the opportunity to strengthen existing nets with mosquito-killing insecticide for free, or exchange damaged nets for new ones.
An estimated 3.5 million nets will be given a new lease of life, increasing the total number of effective nets in the country to 11 million. These will offer years of protection for men, women and children threatened by the deadly disease.
A recent survey showed that nearly one in three bed-nets in Kenya may no longer provide sufficient protection against malaria, with some nets requiring re-treatment every six months.
DFID Minister Ivan Lewis said:
"More than 500 million people across Africa become severely ill with malaria every year, including many children and pregnant mothers. We know bed-nets keep people safe and that is why this Government has made millions of nets available to those most at risk. This scheme will protect families across Kenya for years to come and continues Britain's fight against this deadly disease."
Malaria remains a major killer in Kenya, with close to 70% (24 million) of the population at risk of infection. This weekend's blitz is part of DFID's seven-year, =A360 million drive to combat malaria in the country.
In addition to supplying 12 million nets, the UK has helped supply new drug therapies, improved the country's health system and raised public awareness about the risks of malaria.
Over the last five years, bed-net usage has increased from 4% to 51%. Research indicates that this has led to a 44% cut in child deaths.
The UK has been leading the global fight against malaria. In September Prime Minister Gordon Brown met with leading development figures - including Bill Gates and U2's Bono - to agree a =A31.7 billion action plan that aims to reduce the number of malaria deaths to near zero by 2015.