Abstract: The contents of water soluble K, Zn, Mn and Cu elements were determined in Vigna sinensis plants grown in hydroponic solutions. These solutions have particular matric water potentials ψ (0-1.0 MPa) and amended with K, K-Mn and K-Cu nutrients. The results indicated that water stress showed effects on the contents , relative distribution in different organs and shoot/root ratios of nutrient contents in the investigated plants. Nutrient (Nr) has a dominant role in affecting changes in the contents of micro-nutrients, whereas K content was greatly affected by ψm x Nr interaction. Also, many significant correlations were recorded between various nutrients at different ψm and nutrient treatments. The evaluation and importance of K accompanied with each micronutrient for some physiological aspects of stressed plants were discussed.