Germanium nanowires fabricated by the electrochemical liquid–liquid–solid deposition from water solutions on titanium coated silicon substrate were studied by Raman spectroscopy in order to estimate the heating effect of exciting radiation. The Stokes to anti‐Stokes ratio was determined for crystalline Ge wafer and for nanowires with different mean diameters at two different excitation wavelengths. It was demonstrated that local heating by exciting laser radiation can lead to an increase in temperature sufficiently high for crystallization of initially amorphous Ge nanowires. The results presented may be of great use for fabricating devices, such as metal ion batteries or thermoelectric elements, based on Ge nanowire.