A delay measurement method of a network node device, wherein the network node device comprises a delay measurement apparatus, and the delay measurement method comprises the following steps: a) obtaining (S104, S204), by the delay measurement apparatus, a node delay value of a current packet when a preset time period starts, wherein the node delay value is used to indicate a delay generated when the current packet is forwarded from an ingress port of the network node device to an egress port of the network node device; b) determining (S104, S204), by the delay measurement apparatus based on M+1 boundary values of preset M delay intervals, a delay interval in which the node delay value is located, and adding (S104, S204) 1 to a value of a delay segment counter corresponding to the delay interval in which the node delay value is located, wherein M>1, M is a positive integer, the delay interval in which the node delay value is located belongs to the M delay intervals, and each delay interval corresponds to one delay segment counter; c) repeating (S105, S205), by the delay measurement apparatus, the above steps for subsequent packets forwarded from the ingress port of the network node device to the egress port of the network node device until the preset time period ends; and d1) calculating (S106, S211), by the delay measurement apparatus, a cumulative probability P acc.j, determining (S106, S211) the cumulative probability P acc.j that is greater than or equal to a target probability, wherein the determining is done in such a manner that the calculated cumulative probability P acc.j is greater than or equal to the target probability, and obtaining (S106, S211), as a delay threshold, a node delay value satisfying the target probability, wherein the cumulative probability P acc.j =C acc.j /C total, C acc.j is a sum obtained by accumulating from a value of a first delay segment counter to a value of a j th delay segment counter, 1<j≤M, j is a positive integer, and C total is a sum C total of values of M delay segment counters in the preset time period; wherein d2) the values of the delay segment counters are obtained based on the packets forwarded from the ingress port to the egress port of the network node device during the preset time period, whereas the values of the delay segment counters are accumulated until the cumulative probability P acc.j is greater than or equal to the target probability. a) obtaining (S104, S204), by the delay measurement apparatus, a node delay value of a current packet when a preset time period starts, wherein the node delay value is used to indicate a delay generated when the current packet is forwarded from an ingress port of the network node device to an egress port of the network node device; b) determining (S104, S204), by the delay measurement apparatus based on M+1 boundary values of preset M delay intervals, a delay interval in which the node delay value is located, and adding (S104, S204) 1 to a value of a delay segment counter corresponding to the delay interval in which the node delay value is located, wherein M>1, M is a positive integer, the delay interval in which the node delay value is located belongs to the M delay intervals, and each delay interval corresponds to one delay segment counter; c) repeating (S105, S205), by the delay measurement apparatus, the above steps for subsequent packets forwarded from the ingress port of the network node device to the egress port of the network node device until the preset time period ends; and d1) calculating (S106, S211), by the delay measurement apparatus, a cumulative probability P acc.j, determining (S106, S211) the cumulative probability P acc.j that is greater than or equal to a target probability, wherein the determining is done in such a manner that the calculated cumulative probability P acc.j is greater than or equal to the target probability, and obtaining (S106, S211), as a delay threshold, a node delay value satisfying the target probability, wherein the cumulative probability P acc.j =C acc.j /C total, C acc.j is a sum obtained by accumulating from a value of a first delay segment counter to a value of a j th delay segment counter, 1<j≤M, j is a positive integer, and C total is a sum C total of values of M delay segment counters in the preset time period; wherein d2) the values of the delay segment counters are obtained based on the packets forwarded from the ingress port to the egress port of the network node device during the preset time period, whereas the values of the delay segment counters are accumulated until the cumulative probability P acc.j is greater than or equal to the target probability.