This study developed a natural seasoning (NS) and characterized its food components. Hydrolysate from Alaska Pollock Theragra chalcogramma heads and sea tangle Laminaria japonica byproduct were obtained by incubating them with Neutrase for 4 h. NS was prepared by mixing sorbitol 2%, salt 2%, ginger powder 0.04%, garlic powder 0.2%, onion powder 0.2% and inosine monophosphate (IMP) 0.1% based on concentrated hydrolysates from Alaska pollock head and sea tangle byproduct before vaccum filtering. The proximate composition of NS was 82.7% moisture, 9.0% crude protein, and 5.1% ash. It had a higher crude protein content than commercial anchovy sauce (CS), it was lower in moisture and ash. The 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity and angiotensin-I converting enzyme (ACE) inhibiting activity of NS were 90.1% and 88.9%, respectively, which were superior to those of CS. The free amino acid content and total taste value of NS were 1,626.0 mg/100 mL and 165.86, respectively, which were higher than those of CS. According to the results of taste value, the major free amino acids were glutamic acid and aspartic acid. In the sensory evaluation, the color and taste of NS were superior to those of CS. No difference in fish odor between NS and CS was found.