Powdery mildew is very important foliar disease of cluster bean in major cluster bean growing areas of Karnatakawhich results in huge economic loss. Disease first appears on the leaves at 30 days after sowing and continues to producewhite mycelial growth on various aerial plant parts upto the harvest. Survey results revealed that the disease severity ofpowdery mildew was noticed in all the cluster bean growing areas of northern Karnataka in a low to severe form (13.54 to67.36 %). The disease severity varied with type of cultivation, different stage of the crop and varieties/hybrids grown butthere was no significant difference among the cropping systems. Maximum mean per cent disease index was recorded inDharwad district (39.70 %) whereas, minimum was recorded in Haveri district with 22.92 per cent.