Though Lewis concept of acids and bases is more general than Arrhenius as well as Bronsted-Lowry concepts, yet it has several drawbacks which are discussed below:
1. Lewis concept gives the general idea and includes all the coordination reactions and coordination compounds. This may not be true always.
2. Lewis concept no don explain the behavior of well known protonic acids like HCl, H2SO4, etc. which do not form coordination bonds with bases. Therefore, according to Lewis, these are not regarded as acids.
3. Relative strengths of acids and bases are not explained by Lewis.
4. Many Lewis acids do not possess catalytic property.
5. Lewis Concept does not fit in the acid-base reaction concept.