Soul has white hair swept to one side, and red eyes. He is known for his heavily exaggerated facial expressions and pointed teeth. He naturally has a lazy, droopy, and somewhat uninterested expression on his face. In his first appearance, he wears a yellow and black jacket with buttons going down the front. Around his head is a prominent sweatband that has a sticker with his name on and a round logo featuring a red-lipped mouth bearing pointed fangs surrounded with the letters 'E-A-T.' He wears a pair of maroon pants, and yellow and black sneakers with a pattern on the soles resembling his teeth. In Episode 14, it is revealed that he wears blue boxers with pictures of bones all over them (a reference to Ohkubo's previous manga, B. Ichi). When seen bare-chested or naked, it is shown that he has a large scar going diagonally down his torso from the left shoulder to the right waist. These are from the operation Professor Stein preformed after Crona attacked him during their first encounter.
His soul is light blue with the top resembling his hair and is also the Soul Eater series logo. It can be seen on the back his first jacket.
Beyond Episode 25 and Chapter 24, Soul wears a hairband with new clothing consisting of a black (apparently leather) jacket, an orange T-shirt with the logo on his sweatband emblazoned on the left breast (this may only be visible in episode 49 when he collapses) and a pair of light brown pants, instead of his original headband and old clothing.
In his Spartoi uniform, Soul has kept to his fondness of wearing a jacket. This time, it is a custom, white (possibly military) jacket, with the Spartoi logo on the left shoulder with a small clip strapped to the collar, for closing. Underneath the jacket, he wears a tucked-in, closed, white dress shirt with a tie. He is normally seen without the jacket on. He wears blue pants, white belt, and white shoes.
When he meets with Little Ogre inside his soul in the Black Room, Soul wears a pin-striped black suit with a red dress shirt, black tie, and matching black shoes. He does not wear a hair band in this outfit.
Upon entering the first Chapter of Lust in the Book of Eibon, alongside Maka and other members of Spartoi, his appearance greatly changed in that his gender was switched to female for the remainder of the chapter. In this form, he resembles Maka in appearance, having long hair with a fluffy hairband visible beneath. The clothes are similar to the female Spartoi outfit, with the sailor suit collar, but with the difference that it is more like a dress. He wears a blouse with puffed up sleeves with some subtle flower petal patterns on the hem. The signature tie of the Spartoi uniform has been tied up to be in a bow-shape. He wears a silky skirt that goes down to his knees and white shoes. After reaching the Envy Chapter, he turns straight back to his normal gender.
In Weapon form, he takes on the form of a scythe with a long grey, staff-like haft. Despite probably being of a metal-like material, the haft is capable of bending, sometimes at incredibly drastic angles. The scythe blade is black and red, with the two colours separated by a zig-zagged line going along the blade. Next to the blade is a prominent decor in the shape of an elliptical red eye with a black pupil, framed by a dark grey outline with a line extending out of the outline at the two points of the eye. The eye is capable of moving according to Soul's emotions. It widens when he is surprised, narrows when he is angry, and when he ends up unconscious after being devoured by the Black Blood in the anime, the red eye disappears to signify this. Below the eye is a triangular zig-zagged pattern, split with the colours dark grey and light grey. A slight extension, a bar with three holes punched through it, is seen next to the eye, opposite to the blade.
When Soul becomes a Death Scythe, his Weapon form takes on a slightly different appearance. The prominent eye is now framed by gold metal, which goes around the eye and then splits into two strands of metal, which latch themselves onto the edge of the blade. The slight extension with the three holes is replaced by small wing-shaped objects, one red and one black. These wings can become bigger to enable flight. The blade's curve is also sharper, and the zig-zagged line separating the black and red is gone, with only three zig-zags and the rest a straight line.
Soul also occasionally rides a motorcycle, which acts as a form of alternate transportation for him and Maka. The bike is orange and yellow and is a two-seater for the Weapon and Meister. A small metal ornament in the shape of a monster's head is seen on the front, with the monster's single 'eye' functioning as a headlight. The number plate at the back has his name on it instead. There are red streamers on the handlebars. At the start of the manga, Soul's bike has the same appearance, but later on, its elaborate design changes to the appearance of a regular motorcycle with no distinguishing features in particular.