Parenting Preschoolers (3-5) Support Group
This community is focused on the joys, challenges and concerns faced by parents of preschoolers (3 to 5 year olds). The major areas of child development include: physical development, perception and sensory development, communication and language development, cognitive development, emotional development and social development. Join to share your stories and get advice.

Maybe he thinks the potty will suck him in? If so (and this might sound odd) you will need to prove to him that he potty can't suck him in if that's his problem. Sit yourself on it and flush while on it, then something smaller like a large stuffed animal, then something smaller.
Maybe he's afraid of getting splashed?
One thing I can say on the peeing is: Cheerios. Seriously. Put a handful in the potty and tell him to shoot them. Helps with aim too.