The effect of induced spatial incoherence (ISI) on laser light self‐focusing is investigated using a two‐dimensional Eulerian hydrodynamic plasma simulation code. In homogeneous low‐density plasmas (one‐tenth of the critical density for radiation of wavelength &lgr;L=0.25 &mgr;m) it is found that ISI can effectively eliminate thermal and ponderomotive self‐focusing for a wide range of intensities. In plasma containing an initial linear gradient in density, strong self‐focusing occurs when the maximum intensity in the incident lightI0(whereI0represents the intensity that would be achieved for a perfectly coherent beam) is allowed to approach 1017W cm−2. At lower intensities,I0∼1016W cm−2, thermal self‐focusing is eliminated and ponderomotive self‐focusing is significantly reduced. The dwell time of the filamented light varies from the laser light coherence time to a few tens of picoseconds.