Depending on your beliefs, the mortality of the living body of Jesus ceased when he was crucified by order of Pontias Pilot. The date is ambiguous, 26 to 30 AD/CE. However he was said to have risen from his grave and his spirit transcended into heaven for eternal, spiritual life.
In the four canonical gospels (Matthew, Mark, Luke and John) more information can be found. Scholars however, are still debating the exact date, and with no physical evidence or other corroborative material as of yet; no definitive date has been agreed.
The exact date is likely to be a discussion for quite some time whilst scholars have different views, and quite literally, different schools of thought.
Wikipedia will have more specific information as will other reference sites, and may guide you to arrive at your own conclusion. Also, search engine (i.e. Google), using search terms 'death of Jesus' - 'Jesus Christ' - 'Jesus of Nazareth' or 'The Son of God' may be of further use.