We present a joint spectral and depth domain spectral domain phase microscopy for high-sensitive and high-dynamic-range quantitative phase imaging, where phase information retrieved in spectral domain is used to overcome the limitation of 2π ambiguity and phase information in depth domain is used to achieve a high phase sensitivity. By theoretical derivation and simulation, the sensitivity advantage of phase information in depth domain over phase information in spectral domain is investigated. The theoretical derivation of joint spectral and depth domain spectral domain phase microscopy is presented in detail. The performance of the proposed joint spectral and depth domain spectral domain phase microscopy is illustrated by phase imaging of a coverslip and a resolution target.