According to the duke of Zhou:
Death is a state of peace and stability and a very auspicious sign.
Dreaming of someone else's death or your own death is a good sign of longevity.
Dreaming of your death means that you don't have to worry about your life anymore. If you are healthy, you will live a long life, suggesting that you will start a new life, or you will change in your life and start a new stage of your life.
Dreaming of your own death indicates that there will be more and more wealth and everything will be smooth.
Dreaming that relatives and friends die, the dead relatives and friends will live longer.