The paper describes the investigation of magnetic field treatment on the development of lentil seeds. Stationary magnetic field has been used. The germination energy and germination, length of stems and roots, measured on the 7th and 14th day, as well as the total mass have been used in order to evaluate the effect of magnetic field treatment. The germination energy and germination of seeds have not shown significant differences between variants. The length of stems and roots, measured on the 7th and 14th day, as well as the total mass have shown dependence from the dose of treatment, better expressed for the parameters measured on the 14th day.