Our study provides new information on walleye spawning behavior in impoundment tailwaters. Completion of Harry S Truman Dam (HST) in west-central Missouri, USA, in 1977 blocked a major walleye (Stizostedion vitreum vitreum) spawning migration and flooded the historic upstream spawning area. Creel survey data from 1981–1985, a tagging study, and population monitoring suggested problems with walleye recruitment. Our objective was to determine if walleye spawning movements were affected by fluctuating daily flows from peaking power operations. We used ultrasonic transmitters to monitor walleye movements intensively for eight weeks during spring 1991. We concluded that behavior of walleye in HST tailwaters during spawning season was influenced by water releases, possibly affecting spawning success.