To screen local probiotic strains, 66 cultivable bacterial strains were isolated from water and sediment samples from cultured ponds of sea cucumber () in Dongying in May 2014. Bacterial antagonistic experiments were conducted using V. parahaemolyticus and , which are main pathogenic bacteria of ‘skin ulcer syndrome’ for . In addition, selective medium was used to test the amylase production and protease activities of the isolated strains and to isolate a potential probiotic strain, DY-6. Then, its physiological-biochemical experiments and similarity analysis of 16s rDNA sequences as well as the growth characteristics of DY-6 experiments have been conducted. The safety experiment for the sea cucumber was also proceed. The DY-6 strain was successful in inhibiting V. alginolyticus, as indicated by inhibition zone diameters of 24, 22, 27, and 37 mm, respectively. Meanwhile, the hydrolysis zone diameters of amylase and protease were 28 and 20 mm, respectively. A safety experiment was designed to test the safety of DY-6 for sea cucumber. During the experiment, all sea cucumbers were in good conditions without falling ill. Based on physiological and biochemical experiments and 16s rDNA sequence analysis, strain DY-6 was determined to be 99% similar to B. velezensis. When compared to four bacterial strains isolated from commercial probiotic products, DY-6 exhibited superior growth at 20-35℃ and under salinities of 0 to 35. Moreover, DY-6 came into the logarithmic growth phase after 4 h of cultivation and reached growth peak after 10 h. In summary, strain DY-6 exhibited superb inhibition of sea cucumber pathogens, rapid growth, and both euryhalinous and euryhaline features. Therefore, DY-6 could be used to reduce the occurrence of sea cucumber disease and is also suitable for use at high temperatures during summer and in fluctuation salinity levels, as in the Yellow River Estuary. Thus, strain DY-6 has potential for commercial development.