The study was conducted to compare the early response between the wild (S1), founder (DHLS150), and doubled haploid (DH) lines to salt shock. A single dose of 250 mM NaCl was used to expose the plants to salt shock. Data analyzed at a two-point time; 24 hr post-treatment (24 hr pt), and 14 days post-treatment (2 wk pt) showed a significant increase 24 hr pt in leaf Na+ content (P<0.05) in the parent and DH lines, however, K+ and Ca2+ levels remained significantly unchanged (P>0.05), and K+/Na+ ratio reduced, which indicates osmotic shock. Similarly, the K+/Na+ ratio showed an improvement of 2 wk pt in some of the S1 parent and DH lines, recuperating phase. The qRT-PCR analysis showed significant variation in gene expression, that show an mRNA level of sodium/proton exchanger (NHX1), potassium transporter 9 (KT9) and potassium uptake permease (KUP11), vacuolar H+ adenosine triphosphatase (V- ATPase -G), and chloride gated channel (V-CLC) in both the parent and DH lines. The results further revealed that the S1 and DH lines maintained higher levels of K+, Ca2+, and K+/Na+ ratio in leaves through ion-selective capacity. Therefore, our results conclude that the adaptability of Brassica oleracea to salt shock and prolonged salt stress could be associated with ion selectivity, and Na+ exclusion and the response between the parent and DH lines are similar hence the DH lines can be used for the brassica breeding program.