What is the difference between Red and Black in xiangqi?
These answers restate the rules implemented by our open-source engine, which follows the WXF laws for movement, checkmate and both repetition rulings: a side that forces a repetition by perpetual check or perpetual chase loses rather than drawing. The chase half has not been validated against the official casebook. Where an answer refers to a specific position, that position lives on the linked reference page, where the build verifies it before publishing.
Direct answer
Two things only: Red moves first, and the two sides write at least five of the seven pieces with different characters. Nothing about movement, capture or legality differs. The characters are chosen so you can tell the sides apart at a glance; some pairs sound the same, but not all.
The character pairs
Red / Black: 帥/將 general, 仕/士 advisor, 相/象 elephant, 傌/馬 horse, 俥/車 chariot, 炮/砲 cannon, 兵/卒 soldier.
The general, advisor, elephant, cannon and soldier pairs always differ; many sets write the horse and chariot the same for both sides. Note that the cannon pair is often reversed between sets and books — 炮 and 砲 are both in use for both sides. It never affects play.
What Red's first move is worth
Real but modest. The practical value is the right to set the agenda by playing a Central Cannon on move one, which forces Black to answer rather than choose.
Below expert level the effect is invisible next to the effect of one missed tactic.
Related questions
Is Black at a disadvantage?
Slightly, at high level. Black's job is to equalise, and several defences do that reliably.
Why is one side sometimes green or blue?
Manufacturing preference. The side that moves first is the red one regardless of what colour the other side is printed in.
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