Laser-mutagenesis of -earotene producer Dunaliella salina were investigated. Tie algal survival rate is above 90%. After mutagenesis three mutants were screened, in which the growth rate and length of alga were increased by 20% and 7.5% respectively aa compared with the original D. salina. The productivity of -carotene was 0.48mg-100 ml-1day-1, and waa increased by 19%.