Aids researcher and consultant psychiatrist Dr Sobbie Mulindi succumbed to cancer on Tuesday.
He was 70 years old and had been sick since 2017.
Details on the type of cancer he suffered and where he had been receiving treatment were not immediately available.
Dr Mulindi was a former Deputy Director of the National Aids Control Council (2008-2014) and a senior lecturer in the psychiatry department of the University of Nairobi.
He will be remembered for achievements including helping to reduce the HIV prevalence rate from a high of about 30 per cent in the early 2000s.
He pioneered sensitisation on HIV-Aids among Kenyan youth at a time when it was taboo to talk about sex and HIV.
Dr Sobbie spoke frankly about the correlation between sex and HIV-Aids, constantly warning youth against unprotected sex.
Dr Sobbie was also heavily involved in preparation of the Sessional Paper No. 4 on HIV and Aids in Kenya in 1997.
He also wrote the “HIV/AIDs Situation Analysis” for the Ministry of Health, which facilitated development of its first Strategic Plan on HIV and Aids.
He would later lend his expertise to the development of four National Strategic Plans for HIV/Aids prevention in Kenya and also develop plans for South Africa, Swaziland, Rwanda, Benin, Somalia, Congo and Brazzaville.
In his condolence message, Amani National Congress leader Musalia Mudavadi said, "I have lost a brother, friend and confidant."
"The nation has lost an unrivalled public-spirited academic and intellectual," he added.
Among the many members of the public who have recently died of cancer are Safaricom Chief Executive Officer Bob Collymore, Bomet Governor Joyce Laboso and Kibra member of Parliament Ken Okoth.
As the disease continues to claim many lives, and as Kenya struggles to deal with it, governors have called on President Uhuru Kenyatta to declare it a national disaster.
Council of Governors Chairman Wycliffe Oparanya (Kakamega) on Saturday said that as Kenyans come to terms with the deaths, a chilling realisation is sweeping the country about their vulnerability to the disease.