Objective To find out the benefit and cost of color ultrasonic devices in our hospital after the drop of large equipment examine fee.Methods Data of benefit and cost on 7 color ultrasonic devices in using are collected and analyzed by using Benefit Cost Ratio(BCR) method.Results The higher valuable the equipments are,the more fixed cost they have with lower BCR.Conclusion Buying cheaper equipment is the only way to increase the pure benefit under the precondition of normal diagnosis by devices.