The microalga Haematococcus pluvialis is a natural source of astaxanthin, a red carotenoid that accumulates in the cytoplasm of algal cells under stress conditions and is produced from the transition of motile vegetative cells to non-motile cysts. In industrial astaxanthin production, cyst walls are mechanically disrupted to release astaxanthin, which results in loss of cell viability. In this study, the impact of suborbital flight on H. pluvialis cells was investigated at two growth stages of aplanospore and cyst for the first time. For flight experiments, samples were placed in the bio-capsule during suborbital flight, and then examined in terms of cyst germination, zoospore release, and astaxanthin production after flight. Results showed that 71% of the cyst cells germinated and released zoospores after 2 days post-flight, and the aplanospore cells tended to accumulate pigments. Cell biomass did not change significantly after 7 days of flight. Spaceflight conditions led to a 2.1 and 1.3-fold rise in H2O2 content after 2 and 7 days of flight, respectively. The highest content of astaxanthin (26.1 mg-1 g FW) and phenolic compounds (935.6 mg-1 g FW) was observed in the samples after 7 days of flight. These findings indicate that H. pluvialis can survive spaceflight conditions and may be a promising candidate for inclusion in human life support systems in space.