A self-standing drug-filled synthetic resin ampule (1, 10) comprising an ampule body (2, 7) capable of standing by itself and a drug accommodated inside said ampule body (2, 7), wherein said ampule body (2, 7) has a tip part positioned at an upper part thereof when the ampule body (2, 7) stands by itself, a hollow part (21, 21a, 71) having a drug accommodation portion (23, 78), and a breakable part provided between a lower portion of said tip part and an upper portion of said hollow part (21, 21a, 71); and said tip part has a pressing portion (31, 32) for guiding a pressing force applied thereto in a guiding pressing direction when an operation of breaking said breakable part is performed; said hollow part (21, 21a, 71) has a bottom surface part (4, 4a, 4b) for allowing said ampule body (2, 7) to stand by itself; and said surface part (4, 4a, 4b) has an extension portion (25a, 26a, 31, 32, 41, 41a, 41b, 42, 42a, 42b, 47, 48, 92a, 92b) extended in said guiding pressing direction, characterized in that said tip part has a plate-shaped body portion, said pressing portion (31,32) is formed on the upper portion of the tip part, said pressing portion (31, 32) is formed of upper portions of ribs (31a, 31b, 31c) formed on an outer surface of said plate-shaped body portion by axially extending them, or said pressing portion (31, 32) is formed as a flat plate portion, and wherein a distance from a center of said bottom surface part (4, 4a, 4b) to an outer edge of said extension portion (25a, 26a, 31, 32, 41, 41a, 41b, 42, 42a, 42b, 47, 48, 92a, 92b) extended in said guiding pressing direction is longest of all distances from said center of said bottom surface part (4, 4a, 4b) to outer edges thereof. an ampule body (2, 7) capable of standing by itself and a drug accommodated inside said ampule body (2, 7), wherein said ampule body (2, 7) has a tip part positioned at an upper part thereof when the ampule body (2, 7) stands by itself, a hollow part (21, 21a, 71) having a drug accommodation portion (23, 78), and a breakable part provided between a lower portion of said tip part and an upper portion of said hollow part (21, 21a, 71); and said tip part has a pressing portion (31, 32) for guiding a pressing force applied thereto in a guiding pressing direction when an operation of breaking said breakable part is performed; said hollow part (21, 21a, 71) has a bottom surface part (4, 4a, 4b) for allowing said ampule body (2, 7) to stand by itself; and said surface part (4, 4a, 4b) has an extension portion (25a, 26a, 31, 32, 41, 41a, 41b, 42, 42a, 42b, 47, 48, 92a, 92b) extended in said guiding pressing direction, said tip part has a plate-shaped body portion, said pressing portion (31,32) is formed on the upper portion of the tip part, said pressing portion (31, 32) is formed of upper portions of ribs (31a, 31b, 31c) formed on an outer surface of said plate-shaped body portion by axially extending them, or said pressing portion (31, 32) is formed as a flat plate portion, and wherein a distance from a center of said bottom surface part (4, 4a, 4b) to an outer edge of said extension portion (25a, 26a, 31, 32, 41, 41a, 41b, 42, 42a, 42b, 47, 48, 92a, 92b) extended in said guiding pressing direction is longest of all distances from said center of said bottom surface part (4, 4a, 4b) to outer edges thereof.