The objective was to reveal the spatial and temporal distribution of apple tree fine roots under different water and fertilizer integration modes, explore the regulatory effect of different drip irrigation fertilization strategies on the growth of apple tree fine roots, and provide a theoretical basis for regulating the growth of apple tree fine roots by drip irrigation fertilization mode. In 2019—2021, a two-factor two-level complete combination design field experiment was carried out, the capillary laying method was set up with one row-one tube and one row-two tubes, the fertilization cycle was set for 15d and 30d, and the growth and death of fine roots during the active growth period of apple trees were continuously observed by microroot tube in situ monitoring technology, and the response dynamics of fine root growth and turnover of apple trees to capillary laying mode and fertilization cycle were analyzed. The existing length density and growth of fine roots changed dynamically with the seasons to a unidial curve, and the amount of fine root death was a bimodal curve. The fertilization cycle of 15d significantly increased the existing length density, growth and death of fine roots in time and space distribution compared with the 30d of fertilization cycle. The effect of capillary arrangement on the existing length density and death of fine roots in apple trees did not reach a significant level in time, and the effect on fine root growth changed with seasonal changes. In terms of spatial distribution, the existing length density, growth and death of fine roots in one row-two tubes were significantly greater than those of one row-one tube in the 19~38cm soil layer, and the law was reversed in the soil layer of 57~76cm. The capillary laying mode and fertilization cycle and its interaction had a significant impact on the root turnover rate, the one row-one tube fertilization cycle of 15d can accelerate the turnover of fine roots compared with other treatments. The fertilization cycle had a more obvious regulatory effect on the growth and death of fine roots in apple trees, and the capillary laying method can adjust the spatial distribution of fine roots, and the 15d treatment of one row-one tube fertilization cycle was more conducive to improving the existing length density and growth of fine roots, accelerating the turnover of fine roots, and optimizing the spatial distribution of fine roots.