Efficiency of acetic acid vapours either alone, or in combination with chitosan coating for the controlling gray and blue moulds of apple fruits during storage was investigated . In vitro test results indicated that four concentration of acetic acid vapours i.e. 00, 2.0, 4.0 ,6.0 and 8.0 μl/L were tested against linear growth and spore germination of Botrytis cinerea and Penicillium sp. Results revealed that all concentrations significantly reduced the linear growth and spore germination of B. cinerea and Penicillium sp. Complete reduction in linear growth and spore germination of B. cinerea and Penicillium sp. was obtained with acetic acid vapours at 8.0 and 6.0 μl/L respectively. Complete reduction in linear growth and spore germination of B. cinerea and Penicillium sp. was obtained with chitosan solution at 6.0 and 5.0 g / L respectively. The highest reduction was obtained with chitosan solution at 5.0 and 4.0 g / L which reduced the linear growth and spore germination of both fungi more than 77.8 and 74.2 % respectively. Moreover, In vivo, test, all concentrations of acetic acid vapours significantly reduced the gray and blue moulds as disease incidence or rotted part tissues of apple fruits. The highest reduction was obtained with acetic acid vapour at 6.0 and 8.0 μl/L which reduced the both diseases and rotted part tissues more than 84.0 and 86.0 % respectively. Also, all concentrations of chitosan solutions significantly reduced the gray and blue moulds as disease incidence or rotted part tissues of apple fruits. The highest reduction was obtained with chitosan solutions at 5.0 and 6.0 g /L which reduced the both diseases and rotted part tissues more than 84.0 %. Acetic acid vapour and chitosan solutions alone or in combination significantly reduced the gray and blue moulds as disease incidence or rotted part tissues of apple fruits. The most effective treatment was combined treatment between acetic acid vapour at 8.0 μl/L followed by chitosan solutions at 5.0 or 6.0 g/ L which reduced the both diseases and rotted part tissues more than 84.0 and 87.0 % respectively.