Yes, you should report his Social Security income on a joint return unless his income is Supplemental Security income (SSI) in which case it is not taxable or reportable.

Even if his income is SSI, you should still include him on your joint return.

Married Filing Joint generally yields a better tax result than Married Filing Separate even if one spouse earns little or no taxable income

Generally, filing jointly will give you a bigger refund or less taxes due. When you file separately, your tax rate is higher and you won't be able to claim a number of deductions and credits:

See Is it better for a married couple to file jointly or separately?