A field experiment was conducted from December 2013 to April 2014 in TNAU, Coimbatore to find out the effect of drip fertigation and mulching on WUE, FUE and cost economics of tomato. The data regarding yield, total water used and fertilizer used is collected. The highest yield was found in T3 i.e. 25 micron plastic mulch with 120% RDF. Increased fertilizer use efficiency with the decreased level of fertilizer dose through drip was observed. The highest fertilizer use efficiency of 600.19 kg ha-1 kg of N and K was recorded in T1 (25 micron plastic mulch + 80% RDF), followed by T4 i.e., 50 micron plastic mulch with 80% RDF (561.10 kg ha-1 kg of N and K) and the least efficiency was noted in T9 (284.59 kg ha-1. kg of N and K) i.e., control with 120% RDF. Fertilizer use efficiency of phosphorous was also high in T1 (369.35 kg ha-1. kg of P) followed by T4 (345.29 kg ha-1 kg of P) and the lowest was noted in T9 (189.7 kg ha-1 kg of P). The highest water use efficiency of 43.45 kg m-3 was recorded in treatment T3 which is 25 micron plastic mulch with 120% RDF. The least water use efficiency (21.55 kg m-3) was noted in control (T7). It was because of less yield obtained in the control. Among all the treatments the highest benefit was obtained from treatment T2 i.e. 25 µ mulch with 100 RDF, followed by the treatment T3 and the lowest net return was obtained in control treatment without mulch i.e., T7 (Control with 80% RDF).