The main objective of the study was to find out the psycho-social factors, consequences and mitigation strategies of mental illness. An exploratory and descriptive institutional based cross-sectional study was conducted from September 2017 to September 2018, among three hundred fifty-two (352) families of Persons with mental illness and ten (10) mental health professionals which were selected using availability sampling. The study employed a mixed concurrent triangulation method with the aim of triangulation and consequently to produce a richer and more complete report. A survey questionnaire, FGD guide, and semi-structured interview were developed and used to explore the stated problems. The quantitative data analyzed using mean, percentile ranks, and proportions whereas the qualitative data was analyzed using thematic analysis. The study revealed the psychological factors perceived to cause mental illness, to name the major ones, poor parenting, parental loss, childhood maltreatment, violence, excessive worry for long period of time (frustrations), extreme concern to others, inferiority feelings, low self-esteem, over discouragement of oneself, regret (self-blame), low self-confidence, overconfidence, fail to share ones concern, incongruence between ideal life and actual life, and stressors mainly death of loved one and significant others, unexpected material and financial losses, morass in huge financial indebt, firing from job, and divorce. The study also divulged the sociological (social) factors perceived to cause mental illness which are poverty, unemployment, social deprivation, poor social capital, family disharmony, the culture of dependency on family, unable to establish marriage (being not married), and substance abuse. This study also disclosed the psychosocial consequences PWMI are facing, namely, feelings of inferiority, low self-esteem, anger, shame, embarrassment, regret, excessive worry for having the illness, loneliness, hopelessness, loss of respect, diminished social capital (breakdown of friendship), stigma, discrimination and isolation, mistreatments, insult (humiliation), violation of civil and political rights, suicide, inequalities, challenges to secure employment, poor achievement, and disable to work productively. On the other hand, the study unveiled the psychosocial mitigating strategies Person with mental illness employed as a retort to the psycho-social consequences (challenges) of mental illness they were facing. These were praying to God, moral building (psychological empowerment), encourage the practice of self-looking (introspection), making oneself busy, self-group creation, denial, reaction formation, hide in a home (self-isolation), and being silent (repression). The study finally recommended some measures to curb issues “related to mental illness”and Person with mental illness.