In the "Shincho Koki" (Biography of the Warlord Nobunaga ODA), Yoshimoto's costume during the Battle of Okehazama is described as follows: 'Yoshimoto was dressed in armor with a white cuirass and a five-piece combat helmet decorated with a gold embossed pattern of the legendary dragon Hachiryu; he wore a red brocaded Jinbaori (sleeveless campaign jacket worn over armor), wielded a long sword approximately 85cm long with the inscription of Matsukurago (a sword made by GO no Yoshihiro), a family treasure handed down for generations in the Imagawa family, and a short sword with approximately 55cm in length with the inscription of Dai-samonji (a sword made by Samonji SOZA); he sat straddled upon a jet-black horse of about 166.65cm tall with a gold-rimmed saddle, fixed by a scarlet breeching...'
『信長公記』では義元の桶狭間の戦いの際の出で立ちを「胸白の鎧に金にて八龍を打ちたる五枚兜を被り、赤地の錦の陣羽織を着し、今川家重代の二尺八寸松倉郷の太刀に、壱尺八寸の大左文字の脇差を帯し、青の馬の五寸計（馬高五尺五寸の青毛の馬）なるの金覆輪の鞍置き、紅の鞦かけて乗られける……。」と伝えている。