You will need a visa to enter Uganda. A single entry visa costs USD50 which you are required to pay in cash on arrival at the port of entry. Additional information and a list of visa exempt nationalities can be obtained here http://immigration.go.ug/content/visas-and-passes.
You should apply online for an ‘e-visa’ in advance of travel. You will receive an authorization document by email, which you should print out and give to immigration officials at the port of entry or the Ugandan High Commission in your Country for the visa to be issued.
Your passport should be valid for a minimum period of 6 months from the date of entry into Uganda