A delay measurement device (3) measures a delay time of an end-to-end route path of a virtual private network related to a predetermined user. The delay measurement device (3) includes a measurement route generation unit (31) configured to generate a first route (71) that transfers to a start point node of a route path, transfers back on the route path, and then returns to itself, and to generate a second route (72) of a route that transfers to the start point node of the route path and returns to itself; a packet transmission/reception unit (33) configured to transmit and receive packets circulating on the respective routes generated by the measurement route generation unit (31); a delay measurement unit (36) configured to measure a time from transmission of the packet to reception of the packet by the packet transmission/reception unit (33) to set the measured time as a delay time of the route; and a one-way delay calculation unit (37) configured to calculate a one-way delay time of the route path by subtracting a delay time of the second route (72) from a delay time of the first route (71) measured by the delay measurement unit (36) and dividing the difference by 2.