Suicide remains a significant public health problem for the United States military. Trauma-related diagnoses such as acute stress disorder (ASD) or posttraumatic stress disorder (PTSD) may exacerbate suicide risk, particularly among service members psychiatrically hospitalized following suicide-related events. To date, treatments to address suicide risk and trauma symptomatology among service members within inpatient milieus have been nonexistent. To address this gap, a randomized controlled pilot trial of Post-Admission Cognitive Therapy (PACT) was conducted to evaluate a targeted cognitive-behavioral program among traumatized military personnel (N = 36) hospitalized following a recent suicide attempt. All participants met criteria for ASD or PTSD and were randomly assigned to receive either PACT and enhanced usual care (PACT + EUC) or EUC alone. PACT consisted of six 60- to 90-min individual psychotherapy sessions, adapted from Brown et al.’s (2005) cognitive therapy protocol for suicide prevention. Blinded follow-up assessments were conducted at 1-, 2-, and 3-months postpsychiatric discharge. The primary outcome was days until repeat suicide attempt. Secondary outcomes included depression, hopelessness, suicide ideation, and PTSD symptoms. Participants did not significantly differ in reattempt status. However, based on reliable change index analyses, a greater proportion of PACT + EUC versus EUC participants met criteria for clinically significant change on measures of depression (100% vs. 78%), hopelessness (83% vs. 57%), and PTSD symptom severity (100% vs. 38%), but not for suicide ideation (60% vs. 67%). PACT is an innovative inpatient protocol, currently under evaluation in a well-powered multisite RCT for its efficacy in reducing subsequent suicidal behaviors.