The invention discloses a method for supercritical extraction of 
astaxanthin, which comprises the following steps of: granulating 
haematococcus pluvialis with wall-broken superfine 
powder, loading into an extraction kettle of a supercritical CO<2> extraction device, respectively raising 
temperature and pressure of the extraction device to an extraction condition, starting circular extraction, keeping constant 
temperature and pressure until required extraction time is kept, performing extraction by taking supercritical CO<2> as an extraction agent and 
edible oil as an entrainer in an extractionprocess, and discharging and weighing from a separation kettle after the extraction is finished so as to calculate an 
astaxanthin extraction rate. By the adoption of the method for the supercriticalextraction of the 
astaxanthin, the 
edible oil is used as the entrainer, the astaxanthin in the 
haematococcus pluvialis is extracted by using a supercritical CO<2> extraction technology, and a supercritical CO<2> extraction sample can be directly prepared into an astaxanthin soft 
capsule according to a conventional soft 
capsule filling process. A preparation method provided by the invention has theadvantages of good stability, simple operation, short preparation time, high extraction efficiency, capability of preventing the astaxanthin from being oxidized and degraded and the like; and the astaxanthin soft 
capsule prepared by the extract is safe and nontoxic.