A phase detection method for a clock signal, comprising: sampling, according to sampling periods set by a sampling clock, a clock signal of a clock to be detected; characterized by further comprising: obtaining, according to a mapping relationship between sampled signals and phase angle values, a phase angle value corresponding to a sampled clock signal in a current sampling period; subtracting a phase difference corresponding to the current sampling period from the phase angle value to obtain an initial phase value of the clock to be detected in the current sampling period, wherein the phase difference is a phase difference between the clock to be detected and the sampling clock in the current sampling period, and is calculated according to a relationship between a frequency value of the sampling clock and a frequency value of the clock to be detected, the relationship being φ T = 2 π × mod val sig / val ref, with val sig as frequency of the clock to be detected and val ref as frequency of the sampling clock; and after the sampling ends, obtaining a final phase value of the clock to be detected according to initial phase values obtained in respective sampling periods. sampling, according to sampling periods set by a sampling clock, a clock signal of a clock to be detected; characterized by further comprising: obtaining, according to a mapping relationship between sampled signals and phase angle values, a phase angle value corresponding to a sampled clock signal in a current sampling period; subtracting a phase difference corresponding to the current sampling period from the phase angle value to obtain an initial phase value of the clock to be detected in the current sampling period, wherein the phase difference is a phase difference between the clock to be detected and the sampling clock in the current sampling period, and is calculated according to a relationship between a frequency value of the sampling clock and a frequency value of the clock to be detected, the relationship being φ T = 2 π × mod val sig / val ref, with val sig as frequency of the clock to be detected and val ref as frequency of the sampling clock; and after the sampling ends, obtaining a final phase value of the clock to be detected according to initial phase values obtained in respective sampling periods. obtaining, according to a mapping relationship between sampled signals and phase angle values, a phase angle value corresponding to a sampled clock signal in a current sampling period; subtracting a phase difference corresponding to the current sampling period from the phase angle value to obtain an initial phase value of the clock to be detected in the current sampling period, wherein the phase difference is a phase difference between the clock to be detected and the sampling clock in the current sampling period, and is calculated according to a relationship between a frequency value of the sampling clock and a frequency value of the clock to be detected, the relationship being φ T = 2 π × mod val sig / val ref, with val sig as frequency of the clock to be detected and val ref as frequency of the sampling clock; and after the sampling ends, obtaining a final phase value of the clock to be detected according to initial phase values obtained in respective sampling periods.