Mariko has done the following roles in audio drama.

Battle Girl Ai [CD]	Ai
Clover [CD]	Suzuki Saya
Denshin Mamotte Shugogetten! [CD]	Shugogetten Shaolin
Dirty Pair Flash [CD]	Yuri
Eiyuu Densetsu III -Shiroki Majo- [CD]	Kurisu
Eiyuu Densetsu III -Shiroki Majo- Kenketsu Hen [CD]	Kurisu
Eiyuu Densetsu III -Shiroki Majo- Wakatareta Mizuumi [CD]	Kurisu
Eiyuu Densetsu III Shiroki Majo [CD]	Kris
Fushigi no Kuni no Miyuki chan [CD]	Miyuki chan
Ginga Ojousama Densetsu Yuna Galaxy Wave [CD]	Jinguuji Shiori
GS Mikami [CD]	Okinu
GS Mikami Gokuraku Daisakusen!! [CD]	Okinu chan
Haiyore! Nyaruko-san [CD]	Luhey
Idol Project [CD]	Mimu Emilton
Kanon [CD]	Minase Nayuki
Kanon [CD]	Piro
Kishou Seireiki [CD]	Yumemi
Kouda Mariko no Radio Canvas Special [CD]	?
Makeruna! Makendou [CD]	Madonnaa
MAPS [CD]	Hoshimi
Marmalade Boy [CD]	Koishikawa Miki
Motto! Tokimeki Memorial [CD]	Juuichiya Megumi
Naughty Boy [CD]	?
Pocket Love [CD]	Saiki Ruruna
PopFul Mail Paradise 1, 2, 3, 4, 5 [CD]	Kachuusha
Popful Mail The Next Generation [CD]	Kachuusha
Quo Vadis [CD] {Volume 2-6}	?
Radon [Radio]	?
Samurai Spirits [CD]	?
Seishun Adventure [Radio] {Majotachi no tasogare}	?
Seiyuu daisuki [CD] {Volume 2}	?
Spectral Force 2 [CD]	?
Tarako Pappara Paradise [CD]	Kachuusha
Tarako Pappara Paradise [CD]	Kurisu
Tokimeki Memorial [CD]	Juuichiya Megumi
Tokimeki Memorial Saigo no Natsuyasumi [CD]	Juuichiya Megumi
Tsubasa wo motsu mono [CD]	Kotobuki
Twinbee Paradise [CD]	Madoka
Twinbee Paradise [CD] {3}	Navigator
Twinkle Saber Nova Scramble Star [CD]	Suzunari Hayana
Twinkle Saver Nova [CD]	Suzunari Hayana