The present investigation has been carried out with 70 families in the F3 families with the 7-8 plants in each families derived from the cross IT-38956 xKBC-2to study the extent of association between the physiological parameters such as specific leaf area (SPA/m2) and spad chlorophyll meter readings (SCMR). Estimates of water use efficiency through specific leaf area (SLA), SPAD chlorophyll meter reading (SCMR) assumes greater importance as they are suitable for rapid screening and more affordable and do not hamper the accuracy of determining the water use efficiency. Specific leaf area was significant and negatively correlated with the yield, SCMR also found to be positive and non-significant with the yield. Associations studies indicating that the SLA has having the negative and significant effect, SCMR showing the positive significant effect on the seed yield. The SLA which reflect in the production of higher biomass which is having the negative effect on the seed yield per plant. The production of higher biomass leads to the prolonged vegetative phase and delayed reproductive phase which leads to the lowering the seed yield.SCMR is indicated the positive, direct and low significant effect on seed yield. The indirect positive contribution through plant height, pod length and SLA. These characters will throw some light on the basic physiological studies which are related to the yield. KEYWORDS: Cowpea, SLA, SCMR, Seed yield, Association, correlation