In order to investigate the effects of iodine on the properties of two series of glasses with poor S-based (GeS1.5)100-xIx and (GeS2)100-xIx (x= 5,10,20,30,40), two series of glass samples were prepared by rapid vacuum and high temperature melt quenching. The density, near infrared absorption spectra, transmission spectra, refractive index, optical band gap and thermal expansion were measured and compared. Based on the measured refractive index data, the zero-dispersion point of the material was calculated. The results show that with the addition of iodine, the blue shift is observed in the near-infrared absorption cut-off wavelength, and the glass transition temperature and softening temperature decrease obviously. The transition temperature ranges of the two series are kept near 222~330℃ and 236~332℃, the soften temperature ranges from 267℃ to 375℃ and 282℃ to 364℃, respectively, the expansion coefficient, infrared transmittance and the optical band gap gradually increased. The actual composition of the glass was measured by scanning electron microscopy, and the loss of iodine in the glass raw material was compared with or without liquid nitrogen cooling in process of vacuuming, which shows that the impurity absorption peak intensity in the glass will be enhanced with liquid nitrogen cooling. The glass preparation and purification processes were optimized. Finally, the (GeS1.5)60I40 glass covered by high temperature polymer was drawn and its loss was measured, which is 2.8 dB/m.