Effect of a transverse magnetic field on the suppression of thermal convection was investigated in a vertical column of melt under a destabilizing temperature gradient (β). The melt height and β were 2.5 cm and 16°C/cm, respectively. At , a turbulent thermal convection occurred as measured by a thermocouple inserted in the melt. At , random temperature fluctuations of the turbulent thermal convection assumed some periodic variations. At , a sinusoidal oscillation of 0.17 Hz (10 cpm) and 3°C amplitude appeared. With a further increase in up to 1660G, the amplitude of the oscillation decreased, while the frequency stayed the same. At , no temperature fluctuations were measured, and the thermal convection was completely suppressed. Striation‐free crystal growth was then achieved at , when the thermal convection was suppressed.