Nano‐formulated pesticides are increasingly desired to control the insect pest and plant disease with superior efficacy for guaranteeing the high yield and quality in crop production. However, the impact of nanocarrier morphology on pesticide resistance against rainwash, photolysis, and overall pesticide bioactivity remains unknown. In this work, a series of well‐defined and morphology‐controllable polymer nanocarriers for pesticide are fabricated through polymerization‐induced self‐assembly. All these generated soft nanocarriers with hydrophobic regions exhibit excellent pesticide loading capacity over 70%. After foliar spraying, the generated one‐dimensional worm‐like nanopesticides exhibit an extremely high retention of 80% on leaves after 10 mm rainfall (only 10% for naked pesticide) and a good resistance to photodegradation under UV irradiation (less than 50% for worm‐like micelle vs 70% for naked pesticide degradation after 20 h irradiation under 365 nm). Therefore, worm‐like nanocarriers show higher bioactivity than that of spherical nanocarriers. In general, the comprehensive performance order of pesticide‐loaded polymer nanocarriers is worm‐like micelle > spherical vesicle > spherical micelle. Moreover, the facilely resultant soft nanocarriers of pesticides possess a remarkable low cytotoxicity and excellent biocompatibility in human cells. This nanoplatform possesses simple fabrication, structure controllability, excellent performances, and environmental friendliness, enabling the nanocarriers promising for effective pesticide delivery.