A figure in formal black attire is shown against a deep, dark background, filling the canvas from the chest upward. The face is turned slightly to the figure’s right, with the head set high in the frame and the gaze directed outward. The sitter’s skin appears pale, and the features are painted with soft, natural modeling: faint pink tones touch the cheeks and lips, while the nose and brow are shaped with subtle shading.

The eyes are pale blue and framed by light eyebrows, and the upper eyelids are defined by a gentle shadow. Long, light brown hair falls to shoulder length, parted at the sitter’s left, and curves inward at the ends. A prominent moustache, brushed upward at the corners, and a small patch of beard beneath the lower lip, are rendered in the same light brown as the hair.

The figure wears an elaborate black garment with broad, angular shoulders, decorated with rows of gold embroidery at the upper arms. A stiff, white collar with a sharp, angular edge sits high around the neck, casting a shadow onto the skin below. A gold chain, painted with alternating oval and round links, hangs around the neck and falls down the front of the chest, ending in a gold pendant shaped like a cross or leaf.

The background is painted in a deep, almost uniform brown-black, with no visible objects or architectural details. Light falls from the upper left, illuminating the sitter’s forehead, nose, and the left side of the face, while the right side and the body recede into shadow. The brushwork is smooth and controlled in the face, with more visible, loose strokes in the garment and background, creating a soft contrast between flesh and fabric.

The composition is tightly focused on the upper body, with the head and shoulders dominating the frame and little space around them. Small details, such as the delicate highlights on the chain and the crisp edge of the collar, are picked out with precision against the dark clothing. Philip IV of Spain is painted by Diego Velázquez in 1656.