Abstract: Scholars outside Africa have acknowledged the influence of parenting styles on children�s academic achievement in general and language achievement in particular. It is in line with this trend that this ex-post facto research investigated the impact of parenting style in Primary school pupils� Reading Achievement in South-Western Nigeria. The study involved 2400 primary five pupils form 20 randomly sampled public primary schools in South-Western Nigeria. In addition to some research questions, two null hypotheses namely: There is no significant difference in the reading achievement of pupils from different parenting style and there is no significant variation in the reading achievement of male and female pupils form different parenting style. Two instruments Viz: parenting style Questionnaire and Reading Achievement Test were used for the study. The results revealed that there is no significant difference in the reading achievement of pupils from different parenting style (F_2,2399 = 2.22; p>0.05) and that there is variation in the reading achievement of male and female pupils from different parenting style but the variation is not significant (t-value = 0.913, df = 2370, p>0.05). Based on these findings, it is recommended that in the process of reading instruction, teachers at Primary school level in Nigeria should concentrate on other factors that affect pupils� achievement in reading than parenting styles in their effort to improve reading proficiency of their pupils.