Android 16 - Killed by Cell
Android 17 - When Cell self-destructs Killed by Trunks in the future timeline
Android 18 - Killed in future timeline by Trunks
Android 19 - Killed by Vegeta Killed by Trunks in Dragonball GT
Android 20 (Dr. Gero) - Killed by Android 17 (Yipee!!) Killed by Android 17 in future timeline Killed by Super 17 in Dragonball GT
Babidi - Killed by Mr. Buu
Bardock - Killed by Frieza
Bulma - Eaten by Super Buu (Turned into a chocolate bar)
Cell - Killed by Super Saiya-jin level 2 Gohan
Cell Jr(s) - Killed by SSJ2 Gohan
Chiazou - Killed by Piccolo Daimao Self-destructs in an effort to kill Nappa-sei Killed by Kid Buu Killed by androids in future timeline
Chi-Chi - Killed by Super Buu
Dabura - Eaten by Mr. Buu (Turned into a cookie)
Dende - Killed by Frieza
Dodoria - Killed by Vegeta
Frieza - Killed by Future Timeline Trunks Killed by Goku in future timeline
Garlic - Killed by Kami-sama
Ginyu Force (except Captain Ginyu) - Killed by Vegeta
Gohan - Killed by Kid Buu Killed by androids in future timeline
Gohan (Goku's grandfather) - Killed by Oozaru Goku>br> Goku - Killed by Piccolo (In the fight with Raditsu) Killed by Cell (Self-destruction) Killed by heart disease in the future timeline
Goten - Killed by Kid Buu
Elder Namek - Dies of old age on Namek Dies of old age on Earth
Gyuu Mao (Oxking) - Killed by Super Buu (turned into a chocolate bar)
Kami-sama - Killed by Nappa-sei (Through Piccolo) Killed by androids in future timeline (Through Piccolo)
Kame-sennin (Master Roshi) - Killed by Piccolo Daimao Killed by Super Buu (Turned into chocolate bar)
Korin - Killed by Kid Buu
Kibito - Killed by Dabura
Kid Buu - Killed by Goku (Super Genki-Dama)
King Cold - Killed by Future Timeline Trunks Killed by Goku in future timeline
Kuririn - Killed by one of Piccolo Daimao's henchmen Killed by Frieza Killed by Super Buu (Turned into a chocolate bar) Killed by Android 17 in Dragonball GT (Yahoo!) Killed by the androids in future timeline
Kuwii - Killed by Vegeta
Dr. Myuu - Killed by Bebi Killed by Super 17
Nappa-sei - Killed by Vegeta Killed by Vegeta AGAIN in Dragonball GT
North Kaio (King Kai) - Killed by Cell (self-destruction)
Piccolo - Killed by Nappa-sei Killed by Majin Buu Killed in Earth's destruction in Dragonball GT (destroyed by Bebi) Killed by the androids in future timeline
Piccolo Daimao - Killed by Goku
Popo - Killed by Majin Buu
Puar - Eaten by Super Buu (Turned into a chocolate bar)
Pui Pui - Killed by Vegeta
Raditsu - Killed by Piccolo's Makankosappo
Shen-long - Killed by Piccolo Daimao
Seripa - Killed by Dodoria
Super 17 - Killed by Goku and Android 18
Supopovitch - Killed by Babidi
Tenshinhan - Killed by Nappa-sei Killed by Buu Killed by the androids in future timeline
Trunks (Mirai) - Killed by Cell Killed by Cell in Cell timeline
Trunks (Chibi) - Killed by Kid Buu
Ubuu - Eaten by Bebi
Vegeta - Killed by Frieza Kills himself in an attempt to kill Buu Killed by Android 17 in future timeline
Videl - Eaten by Super Buu (CHOCOLATE AGAIN!!!)
Yajirobe - Killed by Kid Buu Killed by the androids in future timeline
Yamcha - Killed by Saibamen Eaten by Super Buu (CHOCOLATE!!!)
Yamuuh - Killed by Pui Pui
Zaabon - Killed by Vegeta
Characters who never died:
King Yemma
Mr. Buu
Garlic Jr.
Mr. Satan
All the Kaios except for North
East Kaioshin (Supreme Kai)