The Inner Mongolia cashmere goat is a local breed valued for both its cashmere and meat production. Early growth traits include birth weight and weaning weight. Generally, cashmere goats with higher birth and weaning weights tend to exhibit a higher carcass weight at slaughter. Consequently, exploring the genetic variation associated with these early growth traits is crucial in enhancing the meat production performance of Inner Mongolia cashmere goats. For this study, we performed genome-wide association analysis and haplotype analysis on the early growth traits of 212 Inner Mongolia cashmere goats (72 rams, 140 ewes) to identify molecular markers and haplotypes significantly associated with birth and weaning weights. Through genome-wide association analysis and gene annotation, we identified 21 SNPs and 117 candidate genes linked to early growth traits. Notably, genes such as RUNX1T1, ERBIN, MYO15B, NT5C, GRB2, ITGB4, and GALK emerged as significant factors influencing the early growth of Inner Mongolia cashmere goats. Additionally, nine haplotype blocks related to early growth traits were constructed, resulting in eight haplotype combinations. In conclusion, the haplotype combinations A1A1, C1C1, and D1D1 were found to be beneficial for the genetic improvement of early growth traits in Inner Mongolia cashmere goats.