地球上的生物从孕育之初的简单形态，发展到现如今复杂多样的现状这一事实，使人们不由地将生物进化历程等同于从低级到高级，从简单到复杂的发展过程。但是在生物学哲学领域内，对生物进化是否呈现出进步趋势这一论断始终存在争议，不同立场的专家学者就生物进化性进步的标准以及发生机制展开了激烈的讨论。达尔文对于这一问题的回应似乎有些含混不清，这也使得后人对他的观点立场争论不已。本文将结合不同时期，达尔文关于这一问题的具体著作，挖掘分析他对生物进化性进步观念的态度，指出其自然选择理论愈发成熟的同时，达尔文对生物进化性进步这一观点也越来越自信。文章试图论证说明，达尔文本人认同生物进化过程存在进步趋势，并且这种进步性与他的自然选择理论相一致。他给出了生物进化性进步的可能性标准，即生物生理结构的分工和专门化，同时借助生物生存竞争解释了进化性进步这一发展趋势的发生机制，使其符合自然选择理论的整体框架。需要特别指出的是，达尔文所认同的“进步”概念，不同于当时社会主流思潮以及先前生物进化理论中倡导的进步观念。在达尔文看来，生物进化过程体现出的进步性，并不是内在于生物体内部的必然倾向，而是在自然选择过程中发生的随机性、开放性的结果。文章最后，将结合达尔文所处的社会文化背景及其生活环境等因素，尝试对其暧昧不清的立场态度给出可能的推断。

The fact that the creatures on earth have evolved from the simple form at the beginning of the life to the complex and diverse status today, makes people equate the evolutionary process of biology with the development process from low to high, from simple to complex. However, in the field of biological philosophy, there is always controversy about whether biological evolution has shown a progressive trend. Experts and scholars from different positions have engaged in fierce discussions on the criteria and mechanisms of biological evolutionary progress. Darwin's respond on this topic seems to be ambiguous, which has caused future debates on his views and positions. This article will combine Darwin ’s specific texts on this issue at different periods, analyze his attitude to the concept of biological evolutionary progress, and point out that while his natural selection theory is becoming more mature, Darwin become more and more confident in evolutionary progress . The article attempts to demonstrate that Darwin agreed that there is a trend of progress in biological evolution, and that this progress is consistent with his natural selection theory. He gave the possibility standard of biological progress, that is, the division and specialization of biological physiological structure. At the same time, he explained the mechanism of evolutionary progress with the help of biological competition, and made it conform to the overall structure of natural selection theory. It is important to point out that the concept of progress that Darwin agreed with was different from the social trend at that time and the concept of progress advocated by previous theories of biological evolution. In Darwin's view, the progressiveness reflected in the process of biological evolution is not an inevitable tendency inherent in the organism, but a random and open result that occurs during the natural selection process. At the end of the article, I will try to give possibility inferences about his ambiguous stance based on factors such as Darwin's cultural background and living environment.