Even though boron (B) is a micronutrient, it plays a vital role in crop production. Tomato is one of the crops which respond well to B application. Blossom end rot of tomato is due to deficiency symptom of B which affects the economic value of tomato. The present investigation was carried out in Agricultural College and Research Institute, Madurai to evaluate the effect of various levels of application of boron on availability of B and primary nutrients in soil. There were twelve treatments (soil application of B as borax @ 0, 5, 10, 15, 20 & 25 kg ha-1 and foliar application of B as borax @ 0.25 and 0.50 per cent spray twice at 50th and 80th, 60th and 90th and 50th and 90th days after transplanting) which were replicated thrice in randomized block design (RBD). The results revealed that soil application of B as borax @ 20 kg ha-1 recorded the highest available B irrespective of growth stages of tomato. Availability of B decreased with advancement of crop growth stages of tomato. Similarly available nitrogen, phosphorus and potassium status was also found to be high in the above treatment.