Yes he. He refused to obey Allah’s command completely and became rebellious.
(but he rebelled against the command of his Lord) Al-Kahf 18: 50
(And ‘remember’ when We said to the angels, “Prostrate before Adam,” so they all did–but not Iblis, who refused and acted arrogantly, becoming unfaithful) Al-Baqarah 2:34
نعم الشيطان كافر . لأنه خرج عن طاعة الله بالكلية و اعترض على الأمر الإلهي
( ففسق عن أمر ربه)
الكهف 18: 50
( وَإِذْ قُلْنَا لِلْمَلَائِكَةِ اسْجُدُوا لِآدَمَ فَسَجَدُوا إِلَّا إِبْلِيسَ أَبَىٰ وَاسْتَكْبَرَ وَكَانَ مِنَ الْكَافِرِينَ ﴿٣٤﴾ البقرة 2: 34)