An impulse ship is a spacecraft limited to impulse propulsion.

The Bajoran Militia employed impulse ships of various designs. In 2375, the Bajoran Provisional Government deployed twelve of those vessels in a blockade around Derna, commanded by Colonel Kira Nerys, to prevent the Romulans from supplying weapons to their hospital complex. The move was largely symbolic, as the ships themselves posed little military threat to the Romulans. (DS9: "Shadows and Symbols")