You Do Need power plug adapter while traveling from Singapore to Bangladesh.

Here is Why You Need An Adapter

The outlet and plug type used in Bangladesh are A, C, D, G and K and in Singapore is G. This is how they look like.

Singapore

In Singapore, outlets of type G are in use.

Type G

Bangladesh

In Bangladesh, outlets of type A, C, D, G and K are in use.

Type A

Type C

Type D

Type G

Type K