This Bhagavad Gita mp3 audio in Bengali is provided by the Yatharth Geeta website. Each 18 chapter of the Bhagavad Gita is divided into different mp3 files. The translation and explanation in Bengali is provided by Shri Paramahansji Maharaj.
The size of the files vary from 20 MB to 44 MB. You will have to download several files to get the complete Bhagavad Gita with commentary in Bengali.
Each chapter is divided into two separate files. All eighteen chapters are available for download.
You can download Bhagavad Gita MP3 in Bengali here atyatharth geeta.