Abstract: Mikania micrantha is a highly invasive plant species in tropical and subtropical regions. To analyze the adaptability and plasticity of climbing and prostrating M. micrantha plants, we here performed field experiments on morphological characteristics, biomass allocation and reproduction of growth patterns under different environmental moisture conditions. Under moist conditions, climbing plants showed more biomass in the main stem and less in the branches than did prostrating plants. Under dry conditions, climbing plants invested less biomass in the main stem and branch than did prostrating plants. Under both wet and dry conditions, climbing plants had a reproductive investment of 0.429 and 0.342 g·g^–1, respectively, which was significantly higher than that of prostrating plants under the same conditions. Sexual reproduction was the most important approach for climbing plants to produce offspring, which in wet and dry habitats accounted for 84.7% and 62.6%, respectively, of the population. Prostrating plants relied mainly on asexual reproduction to increase their population, with only 40.4% and 35.9% of the population produced by sexual reproduction in wet and dry habitats, respectively. Growth patterns and soil moisture had a significant impact on the biomass and reproduction allocation in plants. Climbing and prostrating M. micrantha plants use different reproductive strategies to adapt to environmental moisture conditions.