Soft X ray laser radiation ranged from 40 nm to 110 nm is obtained by the 7th to the 19th order harmonic generation in krypton with femtosecond Ti∶sapphire laser operating at 780 nm, and the same phenomena especially the spectral shift is observed after the central wavelength of Ti∶sapphire laser is tuned to 795 nm. So the high order harmonic generation is confirmed. The spectrum change pumped by linear polarization laser and the spectrum intensity change with gas pressure are also observed.