It was said that after Ashina Simo returned to the Tang capital Chang'an (implying that this is after the end of the campaign in fall 645), he died.
Dikatakan bahwa setelah Ashina Simo kembali ke ibukota Tang, Chang'an (menyiratkan bahwa ini setelah akhir kampanye pada musim gugur 645), dia meninggal.