Movie posters, as the frontline marketing tools, significantly shape audience expectations and perceptions, making their analysis crucial for understanding broader industry trends. This study quantifies "gender bias" in movie posters, defined through the disproportionate representation and prominence of male versus female characters, considering their visibility, spatial positioning, and size. Employing novel analytical techniques, we examined a dataset of 167,322 movie posters and observed a prevalent male bias. This bias is consistent across genres, geographical regions, and decades, though variations exist: action and adventure genres display pronounced male bias, while romance genres show more balanced representations. Additionally, movies exhibiting male bias tend to achieve higher box office revenues and ratings. Despite the study's constraints, such as its binary gender approach and focus on a single poster version, our findings underscore the need for addressing gender representations in movie marketing materials and suggest avenues for future research in this domain. Bias Scores of Movie Posters and Movie Dialogue. The map visualization displays the geographic distribution of the countries analyzed in our study and highlights their respective correlation coefficients. The color represents the correlation coefficient, with warm colors indicating a positive correlation and cool colors indicating a negative correlation.The intensity of the color reflects the magnitude of the correlation coefficient, with darker shades indicating a stronger correlation. . . . 5.1 Temporal Evolution of Male Bias Ratio in Movie Posters: The line plot showcases the annual variation in the male bias ratio observed in movie posters between 1960 and 2019.