In Indonesia, blasphemy charges have been expanded since the 2000s, and targets and methods of application have diversified. While the main target of blasphemy charges in the past was Muslims, it has recently been extended to include non-Muslims, and blasphemy against online materials has also been prosecuted. The widespread application of blasphemy has prompted radical Muslims to realize the effectiveness of this law, which can act as a ready-made sanction against individuals, groups and even non-Muslims who support different Islamic interpretations. As the cases of blasphemy spread through the media, the public also became aware that the blasphemy could be charged for every aspect of religious life, which resulted in strengthening self-censorship. After the background of enacting blasphemy law is explored, this paper examines the ways it is applied and enforced, focusing on recent cases. It will be maintained that blasphemy, which has begun to apply to non-Muslims, has reduced religious freedom and has decreased the degree of socio-cultural tolerance. The situation, where the Islamic perspective is employed as a key to define inter-religious relationship and religious freedom, allows us to recognize the long-term impact of Islamization on Indonesian society, as opposed to the past where religious tolerance was taken for granted as a characteristic of Indonesian society.