A method for manufacturing a high strength electric resistance welded pipe having a yield strength YS of 450 MPa or more, in which an electric resistance welded pipe is manufactured by continuously forming a hot rolled steel sheet into an open pipe having an approximately circular cross section using a roll forming method, by performing electric resistance welding in which a vicinity of butt portions of the open pipe are heated up to a temperature equal to or higher than the melting point and welded with pressure using a squeeze roll to make an electric resistance welded pipe having an electric resistance weld zone and by subsequently performing an online heat treatment on the electric resistance welded pipe, the method comprising heating and soaking a steel material having a chemical composition containing, by mass, C: 0.025% or more and 0.084% or less, Si: 0.10% or more and 0.30% or less, Mn: 0.70% or more and 1.90% or less, P: 0.018% or less, S: 0.0029% or less, Al: 0.01% or more and 0.10% or less, Nb: 0.001% or more and 0.070% or less, V: 0.001% or more and 0.065% or less, Ti: 0.001% or more and 0.033% or less, Ca: 0.0001% or more and 0.0035% or less, N: 0.0050% or less, O: 0.0030% or less, optionally one or more selected from among Cu: 0.001% or more and 0.350% or less, Ni: 0.001% or more and 0.350% or less, Mo: 0.001% or more and 0.350% or less and Cr: 0.001% or more and 0.350% or less, and the balance being Fe and inevitable impurities, wherein the condition that Pcm which is defined by equation below is 0.20 or less is satisfied, at a temperature of higher than 1200°C and 1280°C or lower for 90 minutes or more, performing hot rolling under conditions such that the hot rolling reduction in an un-recrystallization temperature range is 20% or more and finish rolling completing temperature is 750°C or higher, cooling the hot rolled steel sheet, in terms of the temperature of the central portion in the thickness direction, down to a cooling stop temperature of 620°C or lower at an average cooling rate of 7°C/sec. or more and 299°C/sec. or less in a temperature range of 780°C to 620°C, coiling the hot rolled steel sheet at a coiling temperature of 595°C or lower and 475°C or higher, subsequently performing a heat treatment under conditions such that the coiled hot rolled steel sheet is subjected to a thermal history in which a cumulative holding time in a temperature range of 480°C to 350°C is 2 hours or more and 20 hours or less, performing the online heat treatment under conditions such that the whole of the wall thickness in the vicinity of the electric resistance weld zone is heated up to a temperature of 800°C or higher and 1150°C or lower and then cooled, in terms of the temperature of a central portion in the wall thickness direction, down to a cooling stop temperature of 620°C or lower at an average cooling rate of 7°C/sec. or more and 299°C/sec. or less in a temperature range of 780°C to 620°C, and further subjected to a thermal history in which a cumulative holding time in a temperature range of 500°C to 360°C is 2 seconds or more and 200 seconds or less, in which Pcm = C + Si / 30 + Mn / 20 + Cu / 20 + Ni / 60 + Cr / 20 + Mo / 15 + V / 10 + 5 ⁢ B where C, Si, Mn, Cu, Ni, Cr, Mo, V and B represent the contents (mass%) of chemical elements respectively represented by the corresponding atomic symbols.