The invention discloses a brewing unit of a coffee maker. The unit comprises a top head and a brewing device; a liquid outlet pipe is arranged in the top head, the top head comprises a fixed part (1) and a movable part (2), and an upper filter screen (3) is fixed onto the movable part (2); the fixed part (1) is matched with the movable part (2) in a sleeving mode, a limit device which prevents the fixed part and the movable part from being separated is arranged between the fixed part (1) and the movable part (2), and a compressed spring (4) is arranged between the fixed part (1) and the movable part (2); the top head further comprises a device used for limiting the rising distance of the movable part (2); an automatic coffee grounds scraping device is arranged on the brewing device. According to the brewing unit of the coffee maker, regardless of the more or less amount of added coffer powder, the top head can guarantee that the coffee powder is subjected to constant pressure in brewing and the compaction degree is identical, and the brewing device of the brewing unit can scrape coffee grounds automatically.