Is salary payable a asset or liability?

The key Word is "payable". This makes salary payable a liability until it is fully paid.

There are two entries for a Salary Payable, the original Journal Entry to record when the payable occurs and the Adjusting Entry to record when the balance is paid.

Entry to record:

Salary Expense (debit) $$$

Salary Payable (credit) $$$

Entry to pay:

Salary Payable (debit) $$$

Cash (credit) $$$

yes