Xavier School's emblem is in the shape of a shield. In heraldic language, this particular shape is called "l'ecu francais" in modern form.

The escutcheon or face of the coat-of-arms is divided by a vertical line. From the observer's point of view, the left side is called the dexter side; and the right side, the sinister side.

The dexter side of the escutcheon represents the school and its aims. On an azure background are two suns, one superimposed on the other. The twelve-pointed silver sun represents China; the gold sun with its eight bundles of rays stands for the Philippines. The blazon of the Society of Jesus is found at the center of the suns - the monogram IHS with the Cross above the Hand the three nails of the Cross below it. This side of the escutcheon means that through Xavier School, the Society of Jesus acts as an integrating force enriching the Philippines with the best cultural traits that can be contributed by the minority which has its origin in China.

The sinister side of the escutcheon has a cardinal red background. It features the blazon of the Xavier family, a member of which is the patron of the school - Saint Francis Xavier. The sinister chief has an inverted crescent checkered black and silver while the sinister base contains a bank which is also checkered black and silver. The exact meaning of the Xavier family's blazon is not known. However, the black and silver checkered bank probably represents the Xavier family, members of which fought valiantly and victoriously over the Saracens, hence, the introduction into the blazon of the inverted crescent with family colors. The red background may mean the blood sacrificed by the family for the victory over the Saracens. Hence it indicates that only at the cost of personal sacrifice can Xaverian ideals of service be realized.

Fr. Matteo Ricci and Paul Hsu Kuang Ch'i

An emblem, however, is incomplete without a motto. Xavier School's motto is "LUCEAT LUX", "LET THE LIGHT SHINE" - an echo of the school's Chinese name, Kuang Chi, after a Christian Chinese convert, Paul Hsu Kuang Ch'I, a Prime Minister in Shanghai who was a friend and disciple of the Italian Jesuit Fr. Matteo Ricci.