A pressurized water reactor containment internal passive heat removal system with at least one cooling water circulation circuit, comprising: - a heat exchanger located inside the containment and comprising an upper header and a lower header interconnected by heat-exchange tubes , - a riser pipeline and a downtake pipeline connected to the heat exchanger, - a cooling water supply tank located above the heat exchanger outside the containment and connected to the downtake pipeline, - a steam relief valve connected to the riser pipeline, located in the water supply tank and connected to the same hydraulically, wherein the upper and the lower headers are divided into heat-exchange tube sections on the assumption that: L / D ≤ 20 , where L is the header section length, D is the header bore, the riser pipeline design provides the minimum riser section height h rs to meet the following criterion: ΔP c res = Δρ rs gh rs + Δρ he gh he , h rs = ΔP c res − Δρ he gh he / Δρ rs g , where ΔP c res is the circuit total hydraulic resistance, h he is the heat exchanger height, g is the gravity factor, Δρ rs = ρ cw − ρ ′ 1 − x + ρ ′′ x , Δρ he = ρ cw − ρ hw , ρ cw is the downtake pipeline water density, ρ hw is the riser pipeline water density in the within the heat exchanger height range, ρ', ρ" are the water and steam saturation density, x is the mean mass steam quality of the two-phase mixture in the riser section. - a heat exchanger located inside the containment and comprising an upper header and a lower header interconnected by heat-exchange tubes , - a riser pipeline and a downtake pipeline connected to the heat exchanger, - a cooling water supply tank located above the heat exchanger outside the containment and connected to the downtake pipeline, - a steam relief valve connected to the riser pipeline, located in the water supply tank and connected to the same hydraulically, wherein the upper and the lower headers are divided into heat-exchange tube sections on the assumption that: L / D ≤ 20 , where L is the header section length, D is the header bore, the riser pipeline design provides the minimum riser section height h rs to meet the following criterion: ΔP c res = Δρ rs gh rs + Δρ he gh he , h rs = ΔP c res − Δρ he gh he / Δρ rs g , where ΔP c res is the circuit total hydraulic resistance, h he is the heat exchanger height, g is the gravity factor, Δρ rs = ρ cw − ρ ′ 1 − x + ρ ′′ x , Δρ he = ρ cw − ρ hw , ρ cw is the downtake pipeline water density, ρ hw is the riser pipeline water density in the within the heat exchanger height range, ρ', ρ" are the water and steam saturation density, x is the mean mass steam quality of the two-phase mixture in the riser section. where L is the header section length, D is the header bore, the riser pipeline design provides the minimum riser section height h rs to meet the following criterion: ΔP c res = Δρ rs gh rs + Δρ he gh he , h rs = ΔP c res − Δρ he gh he / Δρ rs g , where ΔP c res is the circuit total hydraulic resistance, h he is the heat exchanger height, g is the gravity factor, Δρ rs = ρ cw − ρ ′ 1 − x + ρ ′′ x , Δρ he = ρ cw − ρ hw , ρ cw is the downtake pipeline water density, ρ hw is the riser pipeline water density in the within the heat exchanger height range, ρ', ρ" are the water and steam saturation density, x is the mean mass steam quality of the two-phase mixture in the riser section. <EOS>