磷化镓（GaP）是镓的磷化物，是无机化合物，也是半导体材料，其间接能隙为2.26eV（300K）。其多晶的材料为淡橙色。未掺入杂质的单晶芯片会是透明的橙色，但大量掺入杂质的芯片因为吸收自由电子，其颜色会变深。磷化镓无味，不会溶于水。

若要变成N型半导体，需要掺杂硫或是碲，若要制作P型半导体，需要掺杂锌。

磷化镓常用在光学系统中，其折射率在波长262 nm (UV)时为4.30，波长550 nm (green)时为3.45，波长840 nm(IR)时为3.19。

Gallium phosphide (GaP), a phosphide of gallium, is a compound semiconductor material with an indirect band gap of 2.26 eV(300K). The polycrystalline material has the appearance of pale orange pieces. Undoped single crystal wafers appear clear orange, but strongly doped wafers appear darker due to free-carrier absorption. It is odorless and insoluble in water.