Hi, 

This looks like roseslug sawfly damage on the upper leaves and potentially some blackspot starting on the lower leaves. 

The sawfly larvae or small green caterpillar like worms, usually hide underneath the leaves and you can pick them off. Usually if you can reduce the population, natural predators will help with the rest and they leaf damage isn't enough to cause overall harm to the plant. 

The link for the blackspot will have some maintenance suggestions. You can control the spread with a fungicide labeled for roses. You will need to apply every 7-14 days depending on the label directions until the fall. Any heavily damaged leaves you can remove now and it will help prevent the spread. Next spring you can start applications as the leaves start to emerge.

Let us know if you have further questions. 

Emily