Common reed (Phragmites australis) is dominant vegetation of temperate coastal wetlands in northeast China. To studying the link between ecosystem respiration (R_eco) and its influential factors, a multi-year in-situ experiment was carried out in a newly restored wetland during the growing seasons of 2012 to 2014. Total in-situ R_eco was separated into soil microbial and belowground root respiration (R_s + r) and plant respiration (R_plant). The soil microbial respiration rate (R_s) was isolated from R_s + r, making it easier to understand each component of R_eco. With the wetland restoration process, the seasonal average aboveground biomass (dry mass) increased from 411.5 g m⁻² to 2048.1 g m⁻² and the corresponding R_eco increased from 751.78 mg CO₂ m ⁻² h⁻¹ to 2612.41 mg CO₂ m ⁻² h⁻¹. R_plant contributed averagely 69% ~ 71% to R_eco on the whole seasonal scale and the plant activity was strongly seasonal. With 1 g of aboveground common reed biomass (dry weight), approximately 3.6 mg CO₂ would be produced per hour during the sprouting period while it could be as low as 0.3 mg CO₂ during plant senescence period. Inundation regime dominated the contribution of R_s to R_eco and the flooded contribution would lower the R_s contribution to as low as 11%.