In Guy's Metro City stage, if 1 or 2 female characters walk pass in front of Cody in the background, he'll give them a naughty glance which will make Jessica mad and smack his face.
Contributed by ProtoSnake
In the Japanese Aracde version of the game, Evil Ryu has a unique ending. This ending is not present in the English arcade release or console ports of the game, instead Evil Ryu and regular Ryu share the same ending.
Contributed by ProtoSnake
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There's a set of sprites for Zanigief which show him performing a backflip. However, they seem to be unfinished and go completely unused.
Contributed by ProtoSnake
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The background of Ken's stage holds multiple cameo appearances of Capcom characters as guests at Eliza's birthday party.

In addition to the cameo characters, Capcom's chairman and CEO Kenzo Tsujimoto also appears as the servant on the far right.

Furthermore, the teddy bear Strider Hiryu is holding is an homage to a deceased Capcom employee who worked on the cancelled SuperGrafx version of Strider.
Contributed by Mass Distraction