Pyridine is a valuable nitrogen based heterocyclic compound which is present not only in large number of naturally occurring bioactive compounds, but widely used in drug designing and development in pharmaceuticals as well as a precursor to agrochemicals and chemical-based industries. Pyridine derivatives bearing either formyl or amino group undergo Schiff base condensation reaction with appropriate substrate and under optimum conditions resulting in Schiff base as product which behave as a flexible and multidentate bioactive ligand. These Schiff bases are of great interest in medicinal chemistry as they can exhibit physiological effects similar to pyridoxal-amino acid systems which are considered to be very important in numerous metabolic reactions. They possess an interesting range of bioactivities including antibacterial, antiviral, antitubercular, antifungal, antioxidant, anticonvulsants, antidepressant, anti-inflammatory, antihypertensive, anticancer activity etc. and considered as a versatile pharmacophore group. Further, several pyridine-based Schiff bases show very strong binding abilities towards the various cations and anions with unique photophysical properties which can be used in ion recognition and they are extensively used in development of chemosensors for qualitative and quantitative detection of selective or specific ions in various kinds of environmental and biological media. These chapter insights the bioactivity and ion recognition ability of Schiff bases derived from pyridine derivatives.