只可以是physical evidence。

“material”虽然也有物质的意思，但在“material evidence”中，它做的是强调的是“significance（重要性）”，多被译为实质性证据。

这一点由其英文释义即可看出：

A material evidence is a piece of evidence which is important to prove a case. It also follows that a witness giving material evidence is a material witness. For instance, an eye-witness to a criminal incident can be said to be a material witness because he can give credible and material evidence in respect of the incident.

在法律英语中，出现material一词时，也多指“实质的”这类意思，如:

material allegation实质性主张：指对当事人的诉求或答辩来说非常重要的、不可缺少的主张。

material alteration实质性修改；重大修改：１对法律文件所作的变更足以改变该文件的法律含义或法律效果；２未经授权更改书面文件的内容或者对不完整的书面文件的补充，导致对一方当事人义务的变更。

而physical evidence则经常被用于指物证，字典中也多次使用：

1.On the other hand, police have never found a body or any physical evidence connecting him to the crimes he confessed to—and later recanted.

——Master Detective, July 1989,p.38

2. The crime scene team located the knife used in the slaying along with some of Holland’s bloody clothing and other physical evidence.

——True Detective, May 1989, p.

因此，物证用“physical evidence”更好，此外，还有一些表述，如：real evidence、objective evidence等也可以用于表示物证。