A kind of expansion part of expansion type plant cultivating device, including power supply expands mould group, signal expands mould group and light source expands mould group. Power supply, which expands mould group, has two electric power transfer units being electrically connected to each other. Signal expands the signal transmission unit that circuit unit is electrically connected in circuit unit and two of the mould group with an electric connection what power supply expansion mould group. Light source expands mould group and is electrically connected what circuit unit, and issues second LED light group of the blue light to promote photosynthesis of plant to the first LED light group and one for promoting plant growth rate with a sending feux rouges. Thereby, user can select suitable expansion part on demand, and those expand part and can be electrically connected to each other, to form the size and shape for meeting user's demand. In addition, this creation separately provides a kind of expansion type plant cultivating device.一種擴充式植物培育裝置的擴充件，包括電源擴充模組、訊號擴充模組、及光源擴充模組。電源擴充模組具有兩彼此電性連接的電力傳輸單元。訊號擴充模組具有一電性連接於電源擴充模組的電路單元及兩分別電性連接於電路單元的訊號傳輸單元。光源擴充模組電性連接於電路單元，且具有一發出紅光用以促進植物生長速度的第一LED燈組以及一發出藍光用以促進植物光合作用的第二LED燈組。藉此，使用者能依需求選用適量的擴充件，且該些擴充件能彼此電性連接，以形成符合使用者需求的大小與形狀。此外，本創作另提供一種擴充式植物培育裝置。
