Police were called to a flat in George Street, Ryde on Tuesday afternoon.
Officers discovered the body a man in his 30s.
His next of kin have been informed.
A 38-year-old man has been arrested on suspicion of murder and he remains in custody at this time.
Acting Detective Chief Inspector Adam Edwards said: ‘Incidents of this nature are incredibly rare on the Isle of Wight, and we can appreciate that this will cause some community concern.
‘Please be reassured that enquiries are in hand and there is no wider risk to the public.
‘Residents can expect to see an increased police presence in George Street and the surrounding areas while we conduct our investigation.
‘We are urging anyone with information about this death to please make contact with us. We’re particularly keen to hear from anyone that may have seen, or heard, anything out of the ordinary in the area on the evening of Monday 3 January, and into the early hours of Tuesday 4 January.’
Anyone with information is asked to contact police on 101, quoting Operation Amaryllis or 44220003393.
Alternatively, you can contact the independent charity Crimestoppers 100 per cent anonymously on 0800 555 111, or via their anonymous online form at crimestoppers-uk.org.