Sea fennel (Crithmum maritimum L.) is a perennial plant tolerant to the soil salinity and could be used as an alternative culture on salty soils. For successful sea fennel cultivation, it is necessary to test germinability of the seed. In this study, germination tests have been carried out on a population of sea fennel from Lopar, island of Rab, Croatia. Our aim was to examine the effect of seed priming on seed germination, radicle length, radicle surface area, average diameter of radicle and radicle volume of sea fennel under different salt concentrations. Seeds were primed with sodium chloride (NaCl) (50 mM) or distilled water (dH₂O) during seven days after which its germinability and early seedling growth was tested on the germination paper treated with different concentrations of NaCl (50, 100 and 150 mM) and dH₂O as control. Seeds which were primed with dH₂O and 50 mM NaCl solution showed the better performance than non-primed seeds; priming alleviated negative effects of low NaCl concentration.