Two field experiments were conducted at the Experimental and Agric. Res. Center, Fac. of Agric., Mansoura University during the two growing seasons 2012/2013 and 2013/2014 aiming at testing the possibility of partly replacing the costly and hazardous chemical fertilizers with less costly and environment friendly organic and bio-fertilizers to satisfy the fertilizer requirements of Sweet basil (Ocimum basilicum) plants. Results indicated that organic and bio-fertilizers compensated for the omitted chemical fertilizers. With omission of half dose of chemical fertilizers, the best herb fresh and dry as well as essential oil yield were obtained when farmyard manure (FYM) at 30m³/fed was combined with the mixture of effective microorganisms (EM) bio-fertilizer. Essential oil quality was maximum under the fertilizer regime which combined FYM at 30m³/fed with microbein and half dose of the chemical fertilizer where linalool and methylchavicol percents were maximum. Based on the obtained results, it could be concluded that half dose of the chemical fertilizers requirements of sweet basil plants could be replaced by 30m³/fed FYM, preferably, in combination with EM bio-fertilizers to reduce production costs and at the same time maintain herb and essential oil yield as well as enhance essential oil quality.