A spread spectrum clock generator (SSCG) using dual-tone profile and random modulation is presented. By uniformly distributing the PSD with dual-tone profile and random modulation, the power of electromagnetic interference (EMI) is 38dB attenuated in 5000ppm frequency deviation. The proposed circuit operates at a 6-GHz clock. Phase rotator based spread spectrum clock generator eliminates undesired jitter with accurate phase moving. The chip core area is less than $0.5*0.8(mm^2)$ and the core power consumption is 15.8mW at supply of 1.0V.