In order to consider phosphorus (P) limitations in agriculture, research has been carried out on the methods that can improve plant growth and increase the efficiency of P use. A pot experiment was conducted to find the effects of magnetized Ca(H2PO4)2·H2O solutions as P source at concentrations 0, 5, 10, 20 and 40 mg·dm−3 and inoculation with arbuscular mycorrhizal fungi Diversispora versiformis on P use efficiency, growth and photosynthetic pigments in sweet basil. P solutions were treated with magnetic field of 110 mT at 3 dm3·min−1 volumetric flow rate. The results indicated that the growth of basil plant, the number of leaf, leaf area, harvest index and chlorophyll a and b contents significantly increased in the result of fertilization with magnetized P solutions and mycorrhizal inoculation as compared to the control. The application of magnetized P solution at 10 mg P·dm−3 and inoculation of mycorrhizal fungi increased P use efficiency by 18.9% and 23.5%, respectively. Findings of the experiment clearly showed that the use of magnetization of P fertilizer and mycorrhization potentially represent natural ways of promoting growth, P status and chlorophyll content in sweet basil.