A woman who was admitted to a Melbourne hospital earlier this week after eating poisonous mushrooms has died.

The woman, aged in her 50s, picked the death-cap mushrooms in the eastern suburb of Box Hill at the weekend.

She was admitted to the Austin Hospital in a critical condition on Wednesday.

It is believed she was visiting from China.

Heath officials have warned people against picking their own mushrooms, because dangerous varieties can look very similar to those that are safe to eat.

The death cap is a large mushroom with white gills and the base of the stem is surrounded by a cup-shaped sack.