Dennis' father is a workaday aerospace engineer. Henry seems to understand Dennis more than his wife does, especially in affairs of the heart. One example was when a furious Dennis stormed in, saying, "Wimmin can say some of the stupidest things!"; Henry knowingly said to Alice, "Margaret." Another time, while Dennis was watching Gina, he confided to his dad, "There's somethin' about Gina that I can't figger out." Henry wisely advised his son, "Wait." Yet another time, Henry and Alice overhear Dennis tell Gina that she "smelled better than a plateful of peanut butter samwiches". Henry replies, "The ultimate compliment". Like his creator Hank Ketcham, Henry served in the US Navy; his position was as a quartermaster (Helmsman) 2nd class on abattleship. Sometimes, he and Alice will get into arguments (which even show his chauvinistic side at times), but they remain devoted to each other. Among his hobbies are golf, taking naps, fishing, and playing the ukulele and singing old songs with George Wilson. A running gag is that Henry often plays the straight man dupe — either resulting from Dennis's pranks, or because of his own foolishness; once he tried to save money on a Christmas tree by cutting one down in the country — and ended up paying $20.00 ($10.00 for a fine and $10.00 for the owner charging him for the tree.)
Henry is a tall, thin 32-year old man who wears eyeglasses, wears a tie, a suit, and brown shoes (usually).