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Polarization control of dual‐wavelength high peak power Raman lasers based on passively Q‐switched technology and yttrium vanadate (YVO4) crystal are widely used for generating novel laser sources, terahertz wave, material processing, and manipulating microparticles. However, the Raman lasers are usually linear polarization. Here, elliptical polarizations with controllable ellipticity and azimuthal angle are manipulated by adjusting the crystalline orientation of a‐cut YVO4 crystal in a passively Q‐switched Raman laser constructed with a Cr4+,Nd3+:Y3Al5O12 (Cr,Nd:YAG) crystal and a a‐cut YVO4 crystal. The ellipticity of the elliptically polarized dual‐wavelength Raman laser varies in a sinusoid modulation as a‐cut YVO4 crystal rotates with respect to the major axis of the intracavity fundamental laser and increases with applied pump power. The azimuthal angle varies in the same speed as a‐cut YVO4 crystal rotates. Anisotropic behavior of sinusoidal modulation of output power, pulse energy, and peak power is observed as a‐cut YVO4 crystal rotates. There are four peaks and four troughs for ellipticity, output power, pulse energy, and peak power within a 360° rotation of a‐cut YVO4 crystal. This work provides a solid and simple method for developing elliptical polarization controllable dual‐wavelength passively Q‐switched Raman laser with high peak power for various potential applications.

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