Musical fit refers to the fit degree of background music with advertising, consumption environment, and goods' features, which reflects the interaction effect between background music and these commercial elements. Although much is known about the effects of single commercial element, their combined effects are less obvious due to a wide range of interactions of people's perception of multiple commercial elements. The interaction effects between background music and other commercial elements has always been a controversial issue, and different or even opposite results have emerged in empirical studies. In contrast to previous studies that simply emphasized that preferred music promoted positive emotions, the perspective of musical fit emphasizes the music's power to convey information related to commercial elements. Relevancy and expectancy have been identified as key dimensions of fit. Relevancy reflects the extent to which stimulus information is helpful or harmful to clear identification of the target topic and its meaning. Expectation refers to the degree to which stimulus information is consistent with people's preexisting knowledge structures associated with a given topic. To this end, certain types of music may be useful for highly involved consumers who are more actively focused on and critically evaluate the sensory experience of consumption, and music perceived as a “fit” with other commercial elements may be more effective because it corresponds with the consumers' subjective perceptions and expectations of music’s relevance or appropriateness to the commercial elements. The fit between background music and commercial elements can be reflected in three aspects: music characteristics, social implications and cultural implications. Music characteristics of background music can reflect the characteristics of the music itself(including the music is sad or joyful, quiet or lively, light or heavy etc.), which is usually determined by the volume, rhythm, tempo, genre and other basic elements. Social implications of background music which is usually determined by the style of music (i.e., classical music, pop music, rock music, rap music, etc.) can reflect the high or low social status and whether the values are traditional or rebellious. Cultural implications of background music may reflect different countries, nationalities, religions and customs. These fit between background music and commercial elements have an impact on consumers’ congnition, emotion and behaviors. In terms of music characteristics, the high fit between background music and commercial elements can attract consumers' attention, help them form deeper memory of goods and promote consumers' willingness to buy. As for social implications, the fit determines consumers' attitude to brand, mood state, memory and choice of goods. When it comes to the culture implications, the high fit can produce a positive attitude towards brand, boost purchase intention and influence purchase behavior. Future study should explore the effect of more structural attributes of background music; seek the boundary conditions of the promotion effect of background music on consumers; break through the existing theories to explore a deeper theoretical mechanism; and explore the effect and mechanism of music fit on consumers' cognition and emotion.