Parenting skills consistently relate to positive adaptation in research on children experiencing homelessness. Emerging evidence suggests that emotional reactivity, expression, and regulation play a critical role in adaptive parenting behaviors. Studies of emotional reactivity in parents utilize different methods, including self-report, observations, and physiological measures. However, these methods are rarely evaluated together, particularly among disadvantaged families. The present study examined how subjective (i.e., self-report), observed, and physiological measures of parent emotional reactivity relate to each other and to observed parenting behaviors in parent-child interaction tasks comprised of problem-solving and teaching tasks. Participants included fifty 4- to 7-year-old children and their caregivers staying in an emergency homeless shelter. Observed and subjective emotional reactivity were largely uncorrelated, except in the case of positive emotions during problem-solving tasks. Adaptive parenting behavior was predicted by lower subjective and observed negative emotions and higher observed positive emotions during the problem-solving tasks, as well as higher observed positive emotions during the teaching tasks. Physiological reactivity did not relate to parenting behaviors across all tasks. Results suggest differential associations of varying indicators of emotional reactivity with parenting skills in different ways, depending on the type of parent-child interaction. Findings also suggest that positive emotional expression supports adaptive parenting behaviors in an emergency shelter setting.