To provide a planting/seeding machine having a ground preparation device in which a support structure of the ground preparation device is simplified and position of a ground preparation transmission case is optimized.SOLUTION: A ground preparation device 53 includes: a right or left ground preparation transmission case 81； and a ground preparation device 53 having a right or left ground preparation supporting arm. A support case 91 is provided outside of a work transmission case 6 of the work device, and the support case 91 and the work transmission case 6 are connected via intermediate cases 89, 92. A rear part of the ground preparation transmission case 81 is supported to the support case 91 about a lateral axial core P2 in a vertically swinging manner, and a motion of drive shafts 61, 107 of the ground preparation device 53 is transmitted by a transmission mechanism 32, 101, 102, 108 provided between inside of the work transmission case 6, the intermediate cases 89, 92, the support case 91, and the ground preparation transmission case 81.SELECTED DRAWING: Figure 10【課題】整地装置を備えた植播系作業機において、整地装置の支持構造の簡素化、及び整地伝動ケースの配置の適正化を図る。【解決手段】右部又は左部の整地伝動ケース８１と、右部又は左部の整地支持アームとを有する整地装置５３において、作業装置の作業伝動ケース６の外側に支持ケース９１が設けられ、中間ケース８９，９２を挟んで支持ケース９１と作業伝動ケース６とが連結される。整地伝動ケース８１の後部が横軸芯Ｐ２周りに上下揺動自在に支持ケース９１に支持され、作業伝動ケース６と中間ケース８９，９２と支持ケース９１と整地伝動ケース８１との内部に亘って設けられた伝動機構３２，１０１，１０２，１０８により、整地装置５３の駆動軸６１，１０７に動力が伝達される。【選択図】図１０
