Pyropia yezoensis at different harvest times were obtained from Jing Bay, and its nutritional and umami characteristics were analyzed. Crude protein, crude fat, ash, inorganic elements, and amino acid composition were determined to analyze its nutritional characteristics. Free amino acids and flavor nucleotides were determined to calculate the taste active value (TAV) and equivalent umami concentration (EUC), which indicated the umami of P. yezoensis. The results showed that P. yezoensis from Jing Bay had high protein and low fat content. The protein content exceeded 49% in the first and second harvest, indicating that the P. yezoensis had higher nutritional value in the early stage of the harvest. The K content was the highest among the constant elements, while the P content was the lowest. Fe content was the highest among the trace elements; Zn content was higher, and Co content was the lowest. Pb content was significantly lower than the limited requirements of GB 2762-2017. There were significant differences between P. yezoensis from the first, second harvest and the fourth, sixth harvest in terms of essential and total amino acid content (P<0.05). Glutamic acid and hypoxanthine nucleotide played a major role in the umami contribution; the Equivalent umami concentration (in dry basis) of P. yezoensis in the first, second, fourth, and sixth harvests was 239.71, 190.03, 108.05, and 51.56 g MSG/100 g, respectively. P. yezoensis from Jing Bay has high nutritional values and desirable umami characteristics in the early stage of harvest, and thus, has great market potential.