A base mounting assembly and a display device are provided. The base mounting assembly includes a main support on a side of a first device, a base including a pedestal part below the first device and a support post connected with the pedestal part and opposite to the main support, the support post including a first end away from the pedestal part and a second end connecting with the pedestal part, and a cushion block movably provided between the support post and the main support. A distance between the support post and the main support is gradually reduced from the first end to the second end so that when the cushion block is moved between the first end and the second end, a position of the support post relative to the main support is changed, causing a change of a position of the pedestal part relative to the first device.