In this paper are reported the results obtained in twelve experiments comparing various nitrogen sources as mineral fertilizers for cotton. Experiments were conducted for some years, located at different soil types used for cotton in the State of São Paulo. When applying Chilean nitrate, Calnitro IG. nitrato de cal IG and Urecal IG in the furrows together with phosphorus and potassium, the effects obtained were practically the same, except for Urecal IG which showed minor response. With exception of Chilean nitrate, these fertilisers are no more used by farmers presently. In another series of trials Chilean nitrate, ammonium sulphate, Nitrocalcio (ammonium nitrate + calcium carbonate) and urea were applied as dressing after 30 days of planting time. These treatments had about the same results; however treatment with urea had a lower effect.