This study investigates how behavioural finance factors influence individual investors' investment decisions in Nigeria's maritime sector. The study specifically examines how overconfidence, regret effect, herding style, risk perception, and heuristic effect influence investment decision making. The study's data were collected using well-structured questionnaires distributed to 238 respondents, with only 217 valid questionnaires. At the 5% level, we used the Spearman rank correlation coefficient. We discovered that overconfidence, regret effect, herding style, and heuristic effect all have a positive and significant impact on investment decision making. Though risk perception influences individual investors' investment decisions, it is only marginally significant. We conclude that behavioural finance factors have a significant impact on individual investors' investment decisions in Nigeria's maritime sector. The study advises individual investors to analyse and monitor the market rather than making investment decisions based on their intuitions, as this may have an impact on their returns. Individual investors who are new to the market should be actively trained and closely monitored by the Nigeria exchange group.