Sarah Joseph was born into a middle-class Christian family in Thrissur district in Kerala in 1945. She was married when she was 14, but continued her studies through correspondence courses. She joined the collegiate service in 1978. She has humorously described herself as ‘a college lecturer who never attended college'. While in college she took the initiative to organise women support activities and founded an organisation called Manushi. They organised meetings, staged plays and campaigned to bring to public attention the inequities against women.