主族金屬通常只有一種氧化態，而過渡金屬元素則常以多種氧化態存在於化合物中。下表列舉出第四週期的過渡金屬的常見氧化態。

過渡金屬離子	常見氧化態	化合物舉例
\(\ce{Sc}\)	\(+3\)	\(\ce{Sc2O3}\)
\(\ce{Ti}\)	\(+2\)，\(+3\)，\(+4\)	\(\ce{TiO}\)，\(\ce{Ti2O3}\)，\(\ce{TiO2}\)
\(\ce{V}\)	\(+2\)，\(+3\)，\(+4\)，\(+5\)	\(\ce{VO}\)，\(\ce{V2O3}\)，\(\ce{VO2}\)，\(\ce{V2O5}\)
\(\ce{Cr}\)	\(+2\)，\(+3\)，\(+6\)	\(\ce{CrO}\)，\(\ce{Cr2O3}\)，\(\ce{CrO3}\)
\(\ce{Mn}\)	\(+2\)，\(+3\)，\(+4\)，\(+6\)，\(+7\)	\(\ce{MnO}\)，\(\ce{Mn2O3}\)，\(\ce{MnO2}\)， \(\ce{K2MnO4}\)，\(\ce{KMnO4}\)
\(\ce{Fe}\)	\(+2\)，\(+3\)	\(\ce{FeCl2}\)，\(\ce{FeCl3}\)
\(\ce{Co}\)	\(+2\)，\(+3\)	\(\ce{CoO}\)，\(\ce{Co2O3}\)
\(\ce{Ni}\)	\(+2\)，\(+3\)	\(\ce{NiO}\)，\(\ce{Ni2O3}\)
\(\ce{Cu}\)	\(+1\)，\(+2\)	\(\ce{Cu2O}\)，\(\ce{CuO}\)
\(\ce{Zn}\)	\(+2\)	\(\ce{ZnO}\)

若過渡金屬處於較高氧化態，則通常是良好的氧化劑，如 \(\ce{Cr2O7^{2−}} \) 和 \(\ce{MnO4^{−}}\) 等；相反地，若過渡金屬處於低氧化態，則通常是良好的還原劑，如 \(\ce{V^2+}\) 和 \(\ce{Cr^2+}\) 等。