Physical mutagenesis as radiation, electrical field, magnetic field...etc., were inspired to enhance or modify their biological behavior. This work was carried out to detect the change in some properties and chemical constituents of maize (variety S.C.10) and bean (variety Nebraseca ) seeds after exposure to magnetic field such as root weight and length, shoot height, proteins, amino acids and protein banding pattern. The density flux of magnetic field was 0.5 Tesla and exposure times were 15 and 30 min. Seeds were placed at suitable distance between magnetic dipoles. Paper chromatography detected increase in some amino acids as aspartic acid, glutamic acid, and methionine in both maize and bean seeds after exposure to magnetic field. The total protein of maize seedlings decreased by 66% after 30 min of exposure to magnetic field. Protein pattern detected new bands after 30 min of magnetic field exposure in maize and bean. The germination and growth of maize and bean seeds were affected after magnetic field exposure. Root weight of maize was decreased 66% but in bean the decrease of root weight was not significant. The maize shoots were increased 66% and 233% after magnetic field exposure for 15 and 30 min, respectively. The bean shoots increased 27.3% and 63.6% after magnetic field exposure for 15 and 30 min, respectively. The results indicated that the magnetic field can produce plants free of Bacillus sp, increases some amino acids contents and also increases maize and bean shoots growth.