As part of the package, the UK is supporting a shipment of one million vaccines against the deadly disease to the stricken island, the Department for International Development (Dfid) said.
This will bring the UK's total contribution to the Haiti crisis to £8 million.
International Development Secretary Priti Patel said: "As the death toll rises and the scale of this devastating hurricane becomes evident, the UK is continuing to do everything it can to help all those affected by this tragedy.
"With the threat of a major cholera spike growing, global Britain will play its part to ensure expertise and support can make a real difference to people in urgent need."
The funds will also provide shelter kits for 5,000 people as well as equipment to purify water and solar lights for some of the most vulnerable people affected by the hurricane.
A team of Dfid experts are in the region working with NGOs and the UN to help those in urgent need.