Albert Bastiaan (Ab) Harrewijn (Giessen-Nieuwkerk, 22 november 1954 - Utrecht, 13 may 2002) was a Dutch GreenLeft politician. Harrewijn was a preacher, who was a member of the Communist Party of the Netherlands. He was strongly committed to helping people on the lowest ranks of social society: the homeless, those on social security and addicted people. He was active in the CPN at the municipal and provincial level.