Observations of predatory behavior of a carabid beetle,Calosoma sayiDejean, and the striped earwig,Labidura riparia(Pallas), were carried out in soybean fields and the functional responses of adult females of each species to noctuid prey were studied in laboratory and field experiments. EachC. sayifemale consumed ca. 1–3 noctuid pupae each day regardless of numbers available, but consumed more small pupae than large ones.C. sayipreyed upon 0.95±0.23 to 15.20±3.67Anticarsia gemmatalisHübner larvae daily when 1–20 hosts were available, respectively. Pupae on the soil surface and in the soybean canopy were attacked without bias. AdultC. sayiwere crepuscular in their locomotor activity and their larvae were active only during daylight.L. ripariaconsumed ca. 2 noctuid pupae/day and were not inhibited by the presence of the silk cocoon covering the pupae of soybean loopers (Pseudoplusia includens(Walker)). When from 5–100 soybean looper larvae were available daily,L. ripariaattacked 4.51±0.96 to 37.93±16.68, respectively.