In this paper, five groups of stronger hyperfine transitions of iodine molecule (127I2) are reported, which are to our knowledge first observed by us. Frequency separations and relative intensities of each transition are calculated. The calculated results and the observed values match very well. With the calculated results, we assigned the vib-rotational bands of each transition. Because the intensities of the newly observed transitions are hundreds of times stronger than transition R(127)11-5, which is applied to frequency-stabilized He-Ne laser, we use them as reference lines of iodine frequency stabilized tunable diode laser and get an output laser 3mW. This kind of frequency-stabilized diode laser may become a new kind of frequency standard.