The research is motivated by the need to enhance the efficiency of agricultural production in the BRICS+ countries and to ensure their long-term food security amid demographic imbalances, ecological and climatic shifts, and the depletion of natural resource bases. The objective of the study is to identify the evolutionary trajectories of agricultural productivity in the BRICS+ economies, to determine the drivers of differentiation, and to forecast food-security scenarios for the grouping. The analysis employs economic and mathematical methods using panel data from the World Bank for the period 2000–2025. Composite indices of Agricultural Productivity (API) and Agricultural Input Intensity (AII) were constructed using min–max normalization. The methodological toolkit includes Principal Component Analysis (PCA), panel regressions with fixed effects, Holt–Winters exponential smoothing with a damped trend, the Granger causality test, and VAR modelling. PCA reduced the dimensionality of the dataset and isolated two principal components explaining 74.58 percent of the total variance. Cluster analysis revealed four profiles of agricultural systems: highly productive desert economies (UAE, Saudi Arabia), resource-intensive continental giants (India, Brazil), moderately intensive systems (China, Egypt, Iran, Russia), and lagging agricultural economies (Ethiopia, South Africa). Econometric modelling detected β-convergence in API with a coefficient of –0.2391 and a half-life of 2.90 years. For labour productivity per worker the coefficient reached –0.6282 with a half-life of 1.10 years. Irrigated land area (influence coefficient 0.42 in the random-forest model), fertilizer consumption (0.31), and water productivity (0.27) were identified as the key determinants of efficiency. The Holt–Winters forecast to 2031, with extrapolation to 2050, indicates an increase in the average API to 0.44–0.52 under the continuation of current trends. The findings can be used to support strategies for technological cooperation, the creation of a joint agrotechnology transfer facility, and the formation of strategic food reserves, ensuring food security for an estimated 4.8–5.2 billion people by the mid-twenty-first century.