Internal combustion engine comprising an apparatus with variable compression ratio and variable expansion ratio, wherein said apparatus is mounted on an engine crankshaft having a first main journal and a plurality of other orderly placed main journals (12, 13, 14) and a first crankpin and a plurality of other orderly placed crankpins (42, 43, 44) and an assembly of a piston-connecting rod having a bearing bush on a big end of the piston-connecting rod, the engine further having a first supporting cylindrical hole in a first main journal, having an angle (α) between an axis of the first supporting cylindrical hole and the crankshaft, and each of the plurality of the other orderly placed main journals (12, 13, 14) is provided respectively with a supporting cylindrical hole, an axis of each supporting cylindrical hole is either coaxial with or parallel to without overlapping an axis of the crankshaft or forms a non-zero angle between the axis of each supporting cylindrical hole and the axis of the crankshaft, wherein the apparatus comprises an actuating motor fixed on a cylinder block of an engine, a worm connected fixedly coaxially together with the actuating motor, a worm gear meshed with the worm, a sun gear fixed coaxially on the worm gear and mounted pivotally on a crankshaft, a first transmission shaft adapted for being rotatably put into the first supporting cylindrical hole, such that both ends of the first transmission shaft extending out of the first support cylindrical hole, a plurality of transmission shafts (22, 23, 24), each formed correspondingly to each of the plurality of the other orderly placed main journals (12, 13, 14), respectively being rotatably positioned one-to-one in the supporting cylindrical holes, and both ends of each of the plurality of transmission shafts (22, 23, 24) extending out of the support cylindrical holes, a first eccentric sleeve being rotatably sleeved between a first crankpin of the crankshaft and the corresponding bearing bush of the big end of the piston-connecting rod, having an inner cylindrical surface and an outer cylindrical surface, and a center line of the inner cylindrical surface and a center line of the external cylindrical surface not coinciding but having an eccentricity e, a plurality of eccentric sleeves (52, 53, 54), each formed correspondingly to each of the plurality of the crankpins (42, 43, 44), respectively rotatably sleeved between the plurality of crankpins (42, 43, 44) and the corresponding bearing bushes of the big end of the piston-connecting rods, having an inner cylindrical surface and an outer cylindrical surface, a center line of the inner cylindrical surface and a center line of the external cylindrical surface not coinciding but having an eccentricity e, a front gear of the first eccentric sleeve fixed on a front end of the first eccentric sleeve and having a pitch circle center that coincides with the center of the inner cylindrical surface of the first eccentric sleeve, a plurality of front gears of the eccentric sleeves (61, 63, 65, 67), respectively fixed on front ends of the corresponding eccentric sleeves (51, 52, 53, 54) and each having a pitch circle center that coincides with the center of the inner cylindrical surface of the corresponding eccentric sleeve (51, 52, 53, 54), a plurality of rear gears of the eccentric sleeves (61, 62, 64, 66), respectively fixed on a rear end of each of the corresponding eccentric sleeves (52, 53, 54) and each having a pitch circle center that coincides with the center of the inner cylindrical surface of the corresponding eccentric sleeve (52, 53, 54), a planetary gear fixedly mounted on the front end of the first transmission shaft and engaged with the sun gear, a rear gear of the first transmission shaft fixedly mounted on the rear end of the first transmission shaft and engaged with the front gear of the first eccentric sleeve, a plurality of the front gear of the transmission shafts (33, 35, 37) respectively fixed on the front end of each of the corresponding transmission shafts (22, 23, 24) and engaged with the adjacent rear gear of the eccentric sleeves (61, 62, 64, 66), and a plurality of the rear gear of the transmission shafts (32, 34, 36, 38) respectively fixed on the rear end of each of the corresponding transmission shafts (21, 22, 23, 24) and engaged with the adjacent front gear of the eccentric sleeves (61, 63, 65, 67), wherein the angle (α) between the axis of the first supporting cylindrical hole and the crankshaft is not zero (α≠0), or the angle α=0.