Systems and methods for aspect-based sentiment analysis using machine learning methods. An example method comprises: receiving, by a computer system, a custom dictionary comprising a list of lexemes referencing at least one of: a target entity or an aspect associated with the target entity; performing, using the custom dictionary, a syntactico-semantic analysis of at least part of a natural language text to produce a plurality of syntactico-semantic structures representing the part of the natural language text; evaluating, using one or more text characteristics produced by the syntactico-semantic analysis, a classifier function to determine polarities associated with one or more aspect terms; and generating a report comprising the aspect terms and polarities of aspects referenced by the aspect terms.