It means from Wednesday all doctors in England are required to notify their local council or local Health Protection Team (HPT) if they suspect a patient has Monkeypox.
Labs must also notify the UKHSA if the Monkeypox virus is identified in a laboratory sample.
Wendi Shepherd, Monkeypox incident director at UKHSA, said: “Rapid diagnosis and reporting is the key to interrupting transmission and containing any further spread of Monkeypox. This new legislation will support us and our health partners to swiftly identify, treat and control the disease.
“It also supports us with the swift collection and analysis of data which enables us to detect possible outbreaks of the disease and trace close contacts rapidly, whilst offering vaccinations where appropriate to limit onward transmission.”
A large proportion of cases so far have been identified in the gay, bisexual and men who have sex with other men community.
Monkeypox is not normally a sexually-transmitted infection, but it can be passed on by direct contact during sex.
It can also be spread through touching clothing, bedding or towels used by someone with the monkeypox rash.
According to the UKHSA, monkeypox does not usually spread easily between people and the overall risk to the UK population remains low.
Anyone with unusual rashes or lesions on any part of their body, especially their genitalia, should contact NHS 111 or call a sexual health service if they have concerns, it said.
The disease is usually mild but can cause severe illness in some cases.
Symptoms include fever, headache, muscle aches, backache, swollen lymph nodes, chills and exhaustion.
A rash can develop, often beginning on the face, which then spreads to other parts of the body including the genitals.