This comparison is often framed as real wood against cheap substitute, which is not accurate and leads to poor decisions. Both materials are used in excellent furniture and both are used in poor furniture. The question is which one suits the part you are making.
What each material actually is
Solid wood is timber cut from a tree, used through the full thickness of the part. It has grain, it has natural variation, and it moves slightly as humidity changes.
MDF is medium density fibreboard, made by breaking wood down into fine fibres and pressing them with resin into a dense, uniform panel. It has no grain, no knots and no direction, and it is dimensionally stable.
Stability
MDF wins clearly. Because it has no grain direction, it does not expand and contract the way timber does, and it will not warp or split along a grain line.
This is why a large flat panel, a wide cabinet door or a painted surface is usually better in MDF. A wide solid timber panel in a room that goes from humid to dry can cup or crack, and that is the material behaving normally rather than a fault.
Strength
Solid wood wins for structural parts. It has far better screw holding in the edge, it resists bending across a span, and it takes the repeated stress of a joint.
MDF is strong in compression and weaker at the edges, and a screw driven into an MDF edge without proper fixings will not hold under load. This is why chair legs, table frames and load bearing rails are made from timber.
Finish
MDF wins for painted and lacquered surfaces. Its smooth, uniform face takes paint perfectly with no grain to fill and no knots to bleed through. A high quality painted finish is far easier to achieve on MDF than on timber.
Solid wood wins where the material itself is the finish. If you want visible grain, an oiled surface and the character of real timber, only timber does that.
Shaped detail
MDF wins. It machines cleanly in any direction, which makes it the natural choice for profiled doors, fluted fronts, curved edges and routed detail. The same shapes in timber cost considerably more and can show grain tear out.
Repair and longevity
Solid wood wins. It can be sanded and refinished many times, and a damaged area can be repaired invisibly. A well made timber piece can last generations and be restored more than once.
MDF can be repaired and repainted, but a deep dent or a swollen edge is difficult to bring back. It is built to last a long time in normal use rather than to be restored repeatedly.
Moisture
Solid wood handles humidity better in the sense that it swells and shrinks and recovers. MDF absorbs water at an exposed edge and swells permanently.
Moisture resistant grades of MDF exist and perform well in bathrooms and kitchens when the edges are properly sealed. Sealing the edges is the whole point, and it is where cheaper work cuts corners.
Weight
MDF is heavier than most timber for the same volume, which surprises people. For large panels this affects shipping cost, handling on site, and the hardware needed to hang a door.
Cost
MDF is usually less expensive as a material and it produces less waste, since a sheet is used efficiently and there are no knots to work around. Solid timber costs more and the price varies considerably by species.
The finished piece does not always follow the material cost. A beautifully lacquered MDF piece with good hardware can cost more than a simple solid timber one.
The answer most good furniture gives
Look inside a well made piece and you will usually find both. Solid timber for the frame, the legs and the load bearing rails. MDF or another engineered board for the large flat panels, the painted doors and the shaped details. Plywood for backs and drawer bottoms.
That combination uses each material where it performs best, and it is a sign of good design rather than compromise.
How to choose for your project
Choose solid wood when you want visible grain, when the piece is structural, when it must last for decades and be repairable, and for anything that takes daily physical stress such as a chair or a dining table base.
Choose MDF when the surface will be painted or lacquered, when the part is a large flat panel or a shaped door, when dimensional stability matters, and when you want a consistent finish across many units.
When ordering, ask which material is used for which part rather than accepting a single word description. A specification that says solid timber frame with lacquered MDF panels is clear. One that says wood is not.
If you would like help specifying the right construction for a piece, our team in Foshan is glad to work through it with you.