[Objective] The spatiotemporal evolution characteristics of agricultural carbon emissions and their relationship with agricultural economic development in the Yimeng Mountainous area were investigated in order to provide a reference for promoting low-carbon agricultural development at the county level and exploring the pathways to achieve the ‘dual carbon' goals. [Methods] Based on the panel data of Linyi City from 2000 to 2023, four types of agricultural carbon sources, namely, land management, rice cultivation, livestock and poultry enteric fermentation, and manure management, were identified. The carbon emission coefficient method and the Tapio decoupling model were used to explore the spatiotemporal evolution characteristics of agricultural carbon emissions in Linyi City, as well as the decoupling relationship between agricultural carbon emissions and agricultural economic development. [Results] ① The total agricultural carbon emissions in Linyi City increased at first and then decreased. In 2011, the agricultural carbon emissions peaked at 1.52×10⁶ t and decreased to 1.21×10⁶ t in 2023, which was a 20% reduction compared to 2011. The carbon emission intensity of both the planting industry and animal husbandry showed an overall downward trend, with the ranges of 0.22 to 0.74 t/10～4 yuan and 0.23 to 1.02 t/10～4 yuan, respectively.② The carbon emissions from each carbon source and their proportion in the total agricultural carbon emissions ranked as follows: land management(7.84×10⁵ t, 56.39%), livestock and poultry enteric fermentation(3.02×10⁵ t, 21.67%), manure management(2.40×10⁵ t, 17.17%), and rice cultivation(6.65 ×10⁴ t, 4.77%).③ The agricultural carbon emissions and carbon emission intensity in various counties(districts) of Linyi City experienced an evolutionary process from increase to decrease, showing certain regional differences. The overall spatial distribution pattern was characterized by ‘low in the center and high in the south and north'.④ The relationship between agricultural carbon emissions and agricultural economic development in Linyi City improved continuously. The decoupling state evolved from ‘expansive negative decoupling' to ‘weak decoupling' and then to ‘strong decoupling'. In 2023, most counties and districts achieved strong decoupling effects. [Conclusion] Linyi City has made certain achievements in agricultural carbon reduction. All counties(districts) should formulate emission reduction policies and measures according to local conditions to continuously promote the coordinated development of low-carbon agriculture production and the agricultural economy.