The incident is being treated as a death in custody, triggering an internal investigation, Western Australian Police say.
Officers were called to the Perth suburb of Embleton about 12.30am on Friday amid reports the man was behaving erratically.
"Police responded to reports the man had entered a house occupied by people not known to him and had smashed multiple windows at the property," Assistant Commissioner Martin Haime told reporters.
Officers found the man in the home's backyard and attempted to negotiate with him, but he continued to behave aggressively, ignoring their orders.
"A Taser was deployed by an officer during attempts to detain the man," Mr Haime said.
Officers eventually restrained the man and he suffered a medical episode minutes later.
It is understood the man was not conscious or breathing when paramedics arrived at the scene.
Paramedics transported him to Royal Perth Hospital, where he later died.
"Our thoughts are with the man's family and loved ones during this difficult time," Mr Haime said.
"Due to the fact the man had been in police custody prior to his death, officers from the internal investigation unit will investigate his death as a death in police custody."
Officers at the scene provided medical assistance to the man.
A report will be prepared for the coroner.
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