A method of sealing a peripheral frame of a display screen, comprising the following steps: Step S1: providing a display screen, wherein the display screen comprises: a first substrate and a second substrate arranged on the first substrate, and the first substrate comprises a panel zone covered by the second substrate and a peripheral frame located outside the panel zone between an edge of the first substrate and an edge of the second substrate; Step S2: providing a substrate suction-holding platform, wherein the substrate suction-holding platform has an upper surface on which a positioning plate is provided; and a separation and protection film is attached to the upper surface of the substrate suction-holding platform; Step S3: suction-attaching the display screen to the substrate suction-holding platform such that the side of the second substrate that is distant from the first substrate is attached to the separation and protection film and the edge of the first substrate is spaced from the positioning plate by a predetermined gap in the direction parallel to said side of the second substrate; Step S4: using a sealant injection device to inject sealant along and into the gap between the edge of the first substrate and the positioning plate; Step S5: subjecting the sealant to curing; Step S6: terminating suction-attachment of the display screen to the substrate suction-holding platform, removing the display screen from the substrate suction-holding platform and then removing the separation and protection film from the surface of the second substrate; and Step S7: cutting the sealant in a straight linear manner alongside the edge of the first substrate. Step S1: providing a display screen, wherein the display screen comprises: a first substrate and a second substrate arranged on the first substrate, and the first substrate comprises a panel zone covered by the second substrate and a peripheral frame located outside the panel zone between an edge of the first substrate and an edge of the second substrate; Step S2: providing a substrate suction-holding platform, wherein the substrate suction-holding platform has an upper surface on which a positioning plate is provided; and a separation and protection film is attached to the upper surface of the substrate suction-holding platform; Step S3: suction-attaching the display screen to the substrate suction-holding platform such that the side of the second substrate that is distant from the first substrate is attached to the separation and protection film and the edge of the first substrate is spaced from the positioning plate by a predetermined gap in the direction parallel to said side of the second substrate; Step S4: using a sealant injection device to inject sealant along and into the gap between the edge of the first substrate and the positioning plate; Step S5: subjecting the sealant to curing; Step S6: terminating suction-attachment of the display screen to the substrate suction-holding platform, removing the display screen from the substrate suction-holding platform and then removing the separation and protection film from the surface of the second substrate; and Step S7: cutting the sealant in a straight linear manner alongside the edge of the first substrate.