The subject of the investigation was the effect of iron chelates Librel Fe-DP7, Pionier Fe 13 and Top 12 on the state of microelement nutrition of two greenhouse tomato cultivars – Cunero F1 and DRW 5900 F1 – grown in rockwool. The results of the study proved that iron chelates significantly influenced the iron content in the index parts (8-9th leaf from the top) of greenhouse tomato. The highest average iron content – 135.2 mg Fe kg-1 d. m. - was recorded for plants fertilized with nutrient solution containing Librel Fe-DP7 as the source of iron, while significantly lower values were obtained for chelates Top 12 – 123.1 mg Fe kg-1 d. m and Pionier Fe 13 – 128.7 mg Fe kg-1 d.m. Iron chelates significantly affected the state of plant nutrition by manganese, zinc and copper. The highest average manganese and copper contents (251.0 mg Mn kg-1 d. m. and 10.16 mg Cu kg-1 d.m. respectively) were determined in plants fertilized with Librel Fe-DP7. The highest average zinc value (38.8 mg Zn kg-1 d.m.) was found in the leaves of tomato fertilized with the solution containing Pionier Fe 13, while the lowest one featured when Librel Fe-DP7 were used. The index parts of Cunero F1 cultivar were characterized by considerably higher content of iron, manganese and zinc than DRW 5900 F1 cv., except for copper content which showed the same average value for both cultivars.