Thirteen inbred lines of sweet corn with great genetic diversity were used as parents, 42 crossing combinations were made according to incomplete dialed cross. Correlation and path analysis of sugar content and main agronomic characteristics of sweet corn were studied. The results indicated that the sugar content were positively correlated with ear diameter, the average weight of ear, bald length, the correlation coefficient were 0.2984, 0.2223, and 0.2159. Among those characters, the greatest contribution to sugar content was the number of row per ear, the efficient was 0.5789. The second was plant height, the efficient was 0.2408. The greatest indirect effect to sugar content was single ear weight by influencing grain number per row, the efficient was 0.1476. The second was ear height by influencing plant height, the efficient was 0.1424.