The hardest part of treating microorganism-related diseases is finding economical, effective, and environmentally friendly treatments. The bioactive chemical composition and biological application of the aerial portions of Haloxylon salicornicum were evaluated using GC-MS in this study. Eight components from the extracted plant were identified using this approach. 6H-[1]Benzopyrano [4,3-C]isoquinoline-6,11(5H)-dione (11.66%) was the main component after 17.71 minutes. After that, 3-Methyl-4-(2,6,6-trimethyl-1-cyclohexen-1-yl)-3-buten-2-one (6.23%), tetrahydro-4-hydroxy-4-methyl-2H-pyran-2-one (4.89%), 9(Z)-octadecenoic acid (4.60%), 2,5-octadecadiynoic acid, methyl ester (4.52%), and 1-deoxy-d-mannitol (4.12%). After examining retention time data at 13.99 and 17.71 minutes, the most abundant alkaloid components were determined. The above ground parts of H. salicornicum extract had the highest DPPH antioxidant potency, with an IC50 value of 71.35 mg/L and a radical scavenging activity percentage of 62.54%. The most effective zone of inhibition was shown by methanolic extract of H. salicornicum against Staphylococcus aureus, Pseudomonas aeruginosa, Bacillus subtilis, and Escherichia coli (27.61, 20.68, 18.82, and 17.08 mm, respectively), while Enterobacter cloacae, Listeria monocytogenes, and S. epidermidis were less effective. The H. salicornicum plant may be a biological agent, and the next level of study involves pure biochemical isolation and bioactivity testing.