In order to formulate future or short-term or long-term development plans, companies usually need to make financial forecasts and implement corporate decisions. This is common in any field, so building practical financial forecasting and decision-making models that can systematically complete this work has become a major need for many companies. Therefore, this article hopes to build financial forecasting and decision-making models through intelligent algorithms and big data technology, that is, using intelligent algorithms based on comprehensive business evaluation indicators to evaluate and analyze the operating status of the company, thereby making reasonable financial forecasts, and then making reasonable corporate decisions through intelligent decision-making systems based on big data. Finally, this article verified this point of view through comparative experiments. In the comparison between the method in this article and the data mining method, the average return on investment of the former was 29.43%, while the average return on investment of the latter was only 26.90%. It can be seen that even in comparison with other mainstream methods, the method in this article still has advantages. Therefore, through the research of this article, it is confirmed that intelligent algorithms and big data are very suitable for building financial forecasting and decision-making models.