In order to evaluate the carbon emission intensity of ships operating in the Bohai Sea region of China, the navigation data of bulk carrier, tanker, and other ships were used to analyze the carbon intensity indicator such as energy efficiency operation index (EEOI), energy efficiency performance indicator (EEPI), and annual efficiency ratio (AER). The correlations between carbon intensity indicators and key factors such as ship deadweight ton and speed were conducted as well as the annual carbon intensity rating for bulk carriers and tankers. The results show that the three carbon intensity indicators of bulk carriers are generally at the level of 10^-6, while those of tankers are at the level of 10^-5. The EEPI and AER of ship operating are in the order of 10^-4, and the EEOI of other ship is at the level of 10^-3. The carbon emission intensity of bulk carrier is relatively good. The annual rating of bulk carrier and tanker in 2023 was conducted using the AER, with ships above Class C accounting for 80% and 100%, respectively. Using the EEOI and EEPI for evaluation, only 20% of bulk carrier is above Class C, while 50% and 75% of tanker is above Class C. All three indicators of tanker are rated better than those of bulk carrier. Under the current operating condition, the carbon intensity indicator rating of tankers from 2023 to 2026 remains basically above Class C, with good performance in ship rating. However, the proportion of ships that meet Class C requirement for bulk carriers has decreased from 80% to 40%, showing a downward trend. Finally, corresponding carbon reduction measures for ship operation are proposed based on the research results.