The multifunction oil for weapons is a unique product with excellent performances used in military forces of ground, navy and air under various climate conditions. As for its multiple performances the product needs excellent base oil with more kinds of additives. Among them there may be some synergistic or negative interactions that need to be well balanced. During the study various effects were investigated. Finally all the main problems were settled down and the lube oil for weapons with excellent performances in cleaning, lubricating and protecting was obtained.