Mangrove forests provide many ecosystem services to coastal communities and are essential in addressing climate change and coastal erosion. Unfortunately, physical pressures, including timber extraction, firewood, and land conversion to agriculture and aquaculture have threatened this ecosystem. Recognizing the reduction in mangrove coverage, mangrove plantations are widely being utilized in many countries to restore ecosystem services, including capturing and storing atmospheric carbon. However, it is still being determined whether mangrove plantations can sequester carbon as much as natural mangroves. This study investigated the carbon storage potential of the planted mangrove in the Ayeyarwady Region, Myanmar. Field data: the diameter at breast height (DBH) ≥ 5 cm and the total tree height (H) ≥ 1 m of all standing trees within each plot were measured and recorded according to species and were used to calculate biomass and carbon storage. The findings of the present study described that the overall average above- and belowground carbon storage of the mangrove plantation was 100.34 ± 50.70 Mg C ha−1 and 34.76 ± 16.59 Mg C ha−1, respectively. Biomass and carbon storage were closely related to the stand basal area. Among species, the Avicennia officinalis species contributed the highest total biomass carbon accumulation. The average amount of carbon sequestration by the planted mangroves was 495.85 MgCO2-eq ha−1. According to the findings, mangrove plantations could achieve benefits in terms of carbon storage and sequestration in biomass with suitable species selection and management. This finding can be applied to mangrove plantation management at the regional and global levels.