A high strength hot-dip galvanized steel sheet excellent in yield strength and formability, having a steel sheet with a galvanized layer formed on the surface, the steel sheet consisting of a chemical composition by mass% (identical here and hereinafter for chemical composition), C: 0.05 to 0.3%, Si: 1 to 3%, Mn: 1 to 3%, P: 0.1% or less (inclusive 0%), S: 0.01% or less (inclusive 0%), Ti: 0.02 to 0.2%, Al: 0.001 to 0.1%, N: 0.002 to 0.03%, and optionally one or more of: Cr: 0.01 to 3%, Mo: 0.01 to 1%, Cu: 0.01 to 2%, Ni: 0.01 to 2%, B: 0.00001 to 0.01%; Ca: 0.0005 to 0.01%, Mg: 0.0005 to 0.01%, and REM: 0.0001 to 0.01%, and the balance consisting of iron and unavoidable impurities, the steel sheet having a tensile strength of 1,000 MPa or more, a yield strength of 700 MPa or more, and a balance of tensile strength and elongation (total elongation: EL) of TS×EL of 24,000 MPa • % or more, and further satisfying both 10 C + 0.4 Si + Mn ≤ 4.5 and 0.8 × 723 − 10.7 Mn − 16.9 Ni + 29.1 Si + 16.9 Cr + 0.2 × 910 − 203 √ C + 44.7 Si + 31.5 Mo − 30 Mn − 11 Cr − 20 Cu + 700 P + 400 Al + 400 Ti ≤ 780 (where [] means content (mass%) for each of chemical composition) and wherein the microstructure consists of by area ratio based on the entire microstructure (identical here and hereinafter for the microstructure): bainitic ferrite: 40 to 65%, martensite + retained austenite: 15% or more, the martensite: 15% or less, the retained austenite: 5% or more, and ferrite: 20 to 40%, in which a C concentration of the retained austenite (CyR) is 0.9 mass% or more, both of an average grain diameter of recrystallized ferrite and an average grain diameter of sub-grains in un-recrystallized ferrite particles are 3 μm or less and an area ratio of a ferrite having a grain diameter of 5 μm or more is 5% or less and an area ratio of worked ferrite is 5% or less for the ferrite and, further, an average grain diameter of TiC particles present in the ferrite particles is 10 nm or less. Cr: 0.01 to 3%, Mo: 0.01 to 1%, Cu: 0.01 to 2%, Ni: 0.01 to 2%, B: 0.00001 to 0.01%; Ca: 0.0005 to 0.01%, Mg: 0.0005 to 0.01%, and REM: 0.0001 to 0.01%, and bainitic ferrite: 40 to 65%, martensite + retained austenite: 15% or more, the martensite: 15% or less, the retained austenite: 5% or more, and ferrite: 20 to 40%, in which a C concentration of the retained austenite (CyR) is 0.9 mass% or more, both of an average grain diameter of recrystallized ferrite and an average grain diameter of sub-grains in un-recrystallized ferrite particles are 3 μm or less and an area ratio of a ferrite having a grain diameter of 5 μm or more is 5% or less and an area ratio of worked ferrite is 5% or less for the ferrite and, further, an average grain diameter of TiC particles present in the ferrite particles is 10 nm or less. a C concentration of the retained austenite (CyR) is 0.9 mass% or more, both of an average grain diameter of recrystallized ferrite and an average grain diameter of sub-grains in un-recrystallized ferrite particles are 3 μm or less and an area ratio of a ferrite having a grain diameter of 5 μm or more is 5% or less and an area ratio of worked ferrite is 5% or less for the ferrite and, further, an average grain diameter of TiC particles present in the ferrite particles is 10 nm or less.