Maneklal Sankalchand Thacker (1904–1998) was an Indian power engineer, academic and the director general of the Council of Scientific and Industrial Research, the largest research and development organization in India.
He served as a secretary at the Ministry of Scientific Research and Cultural Affairs (present-day Ministry of Culture) (1957–62) and sat in the Planning Commission of India as a member from 1962 to 1967.
He was an elected fellow of the Indian Academy of Sciences and the Indian National Science Academy.
The Government of India awarded him the third highest civilian honour of the Padma Bhushan, in 1955, for his contributions to literature and science education.He was elected as the head of Freemasonry in India in January 1969 and continued till December 1974, after serving 2 consecutive terms as Most Worshipful The Grand Master of the Grand Lodge of India.