A p-type GaAs single crystal containing Si, Zn, B and In as dopants has an average dislocation density of 100 cm.sup.-2 or less. It may be produced by cooling a GaAs melt containing Si, Zn, B and In as dopants in a crystal-growing container having a seed crystal placed at a lower end thereof in an upward increasing temperature gradient, to cause a single crystal to grow upward from the seed crystal.