A method for producing a high-strength hot-dip galvanized steel sheet having a tensile strength of 440 MPa or more, wherein the method is performed in a continuous galvanizing line with a strip speed of 60 mpm or more and 150 mpm or less, said method comprising: subjecting a steel sheet to recrystallization annealing, wherein the steel sheet has a chemical composition containing, by mass percent, Si: 0.1% or more and 2.5% or less, Mn: 1.0% or more and 3.0% or less, C: 0.3% or less, P: 0.100% or less, and S: 0.010% or less, and optionally one or two or more selected from Al: 0.01% or more and 1.0% or less, Mo: 0.05% or more and 1.0% or less, Nb: 0.005% or more and 0.05% or less, Ti: 0.005% or more and 0.05% or less, Cu: 0.05% or more and 1.0% or less, Ni: 0.05% or more and 1.0% or less, Cr: 0.01% or more and 0.8% or less, B: 0.0005% or more and 0.005% or less, Sb: 0.001% or more and 0.10% or less, and Sn: 0.001% or more and 0.10% or less, the balance being Fe and incidental impurities, then subjecting the steel sheet to immersion in a hot-dip galvanizing bath having effective Al concentration of 0.07% or more by mass and 0.170% or less by mass to perform hot-dip galvanization, wherein the effective Al concentration in the bath is a value obtained by subtracting the concentration of Fe in the bath from the concentration of Al in the bath, subsequently subjecting the steel sheet withdrawn from the hot-dip galvanizing bath to coating weight adjustment; applying ultrasound having a frequency of 10 kHz or more to the steel sheet from an ultrasonic oscillation member having an amplitude of 10 μm or less for 0.010 seconds or more and 0.500 seconds or less during a period from a start of the immersion to an end of the coating weight adjustment, the ultrasonic oscillation member being in contact with molten zinc and set at a distance of 0 mm or more and 30 mm or less from the steel sheet, wherein the time for applying the ultrasound is the time when the steel sheet lies in the range where the perpendicular distance from the surface of the steel sheet to the ultrasonic oscillation member is within 30 mm, and; subjecting a hot-dip galvanized layer of the steel sheet after the coating weight adjustment to alloying treatment for 10 seconds or more. subjecting a steel sheet to recrystallization annealing, wherein the steel sheet has a chemical composition containing, by mass percent, Si: 0.1% or more and 2.5% or less, Mn: 1.0% or more and 3.0% or less, C: 0.3% or less, P: 0.100% or less, and S: 0.010% or less, and optionally one or two or more selected from Al: 0.01% or more and 1.0% or less, Mo: 0.05% or more and 1.0% or less, Nb: 0.005% or more and 0.05% or less, Ti: 0.005% or more and 0.05% or less, Cu: 0.05% or more and 1.0% or less, Ni: 0.05% or more and 1.0% or less, Cr: 0.01% or more and 0.8% or less, B: 0.0005% or more and 0.005% or less, Sb: 0.001% or more and 0.10% or less, and Sn: 0.001% or more and 0.10% or less, the balance being Fe and incidental impurities, then subjecting the steel sheet to immersion in a hot-dip galvanizing bath having effective Al concentration of 0.07% or more by mass and 0.170% or less by mass to perform hot-dip galvanization, wherein the effective Al concentration in the bath is a value obtained by subtracting the concentration of Fe in the bath from the concentration of Al in the bath, subsequently subjecting the steel sheet withdrawn from the hot-dip galvanizing bath to coating weight adjustment; applying ultrasound having a frequency of 10 kHz or more to the steel sheet from an ultrasonic oscillation member having an amplitude of 10 μm or less for 0.010 seconds or more and 0.500 seconds or less during a period from a start of the immersion to an end of the coating weight adjustment, the ultrasonic oscillation member being in contact with molten zinc and set at a distance of 0 mm or more and 30 mm or less from the steel sheet, wherein the time for applying the ultrasound is the time when the steel sheet lies in the range where the perpendicular distance from the surface of the steel sheet to the ultrasonic oscillation member is within 30 mm, and; subjecting a hot-dip galvanized layer of the steel sheet after the coating weight adjustment to alloying treatment for 10 seconds or more.