This study was conducted during two successive seasons (2012/2013 first ratoon  and 2013/2014  second  ratoon) on Williams  banana    cultivar grown in clay loam soil under flood irrigation system in a private banana orchard located at El-Hagabey  district, Meet Ghamr  Dakahlia Governorate, at 3x3.5 m apart.  Forty  five  stools/(mat) ,each containing two plants of Williams  cultivar were chosen to evaluate the effect of   foliar  spray  with Cobalt , Vit B₁₂ and  ascorbic acid ( Vit C) singly, double or in triple combinations, beside control treatment   on yield and  fruit quality  of the tested Williams banana cv. These treatments were arranged in a randomized complete blocks design with three replicates. The obtained results could be summarized as follows:Sprayed banana plants with the mixture of  cobalt  sulphate  + Vit B₁₂+ Vit C at 50+50+500 ppm each  (T₁₄) recorded increases in bunch weight,  yield /fed. and  number of fingers /bunch  were about 63.34  , 65.49  and   15.22 % over control treatment, respectively. The plants which sprayed with  the mixture of cobalt sulphate  + Vit C at 100+1000 ppm each (T₁₁) gave the highest values  of  hand and  finger weight and recorded increases about 54.00 and 62.82% over control  treatment, respectively .The  highest values of  total sugars , SSC/TA and Vit.C  were obtained by the plants which sprayed with cobalt sulphate  + Vit B₁₂+ Vit C at 100+100+1000 ppm each (T₁₅)  average two seasons  and recorded the relative increases  were about   24.62, 100.56  and  44.34% over control, respectively.