Every organisation desire to grow. When the relationship existing in an organisation is not cordial, it obstructs the organisational growth. Hence, the study observes mentoring and relational growth of the Pentecostal churches. Confrontive, and relationship mentoring was related to nurturing, proclaiming and witnessing in the Pentecostal churches in Nigeria. The study adopts a cross-sectional survey design. The population comprises the 4502 workers of the 150 churches registered with PFN and the sample size of 354 was determined with Krejcie and Morgans’ (1970) table. The sample subjects were got through Simple Random Sampling technique. Data were got through a self-administered questionnaire and the Spearman’s Rank Order Correlation Coefficient was used to analyze the hypothetical statements. The findings revealed positive and significant relationships between mentoring and all the measures of relational (nurturing, proclaiming, and witnessing) growth. The study concludes that mentoring significantly relates to the relational growth of churches and recommends enhancement of relationship and confrontive mentoring for relational growth of the church