This study examines the stress-strain and acid-resistance of pine needle ash (PNA) concrete. Materials used for this experiment are PNA, normal portland cement, natural fine and coarse aggregate. Test results show that the highest static modulus of elasticity are achieved by 5% PNA filled PNA concrete. Acid-resistance of PNA concrete is increased with increase of the content of PNA. It is 1.29 times of the normal cement concrete for 5% PNA filled PNA concrete and 2.57 times for 15% PNA filled PNA concrete, based on the elapsed days for 25% mass loss of original mass immersed in the 5% H₂SO₄ solution. Accordingly, PNA concrete will greatly improve the properties of concrete.