There are three red giants in the constellation that are visible to the naked eye. Mu Cephei, also is known as Herschel's Garnet Star due to its deep red colour. It is a semiregular variable star with a minimum magnitude of 5.1 and a maximum magnitude of 3.4. Its period is approximately 2 years. The star is around 5.64 AU in radius. If it were placed at the center of the Solar System, it would extend to the orbit of Jupiter. Another, VV Cephei A, like Mu Cephei, is a red supergiant and a semiregular variable star, located at least 5,000 light-years from Earth. It has a minimum magnitude of 5.4 and a maximum magnitude of 4.8, and is paired with a blue main sequence star called VV Cephei B. One of the largest stars in the galaxy, it has a diameter 1,400 times that of the Sun. VV Cephei is also an unusually long-period eclipsing binary, but the eclipses, which occur every 20.3 years, are too faint to be observed with the unaided eye. T Cephei, also a red giant, is a Mira variable with a minimum magnitude of 11.3 and a maximum magnitude of 5.2, 685 light-years from Earth. It has a period of 13 months and a diameter of between 329 to 500 solar diameters.
There are several prominent double stars and binary stars in Cepheus. Omicron Cephei is a binary star with a period of 800 years. The system, 211 light-years from Earth, consists of an orange-hued giant primary of magnitude 4.9 and a secondary of magnitude 7.1. Xi Cephei is another binary star, 102 light-years from Earth, with a period of 4,000 years. It has a blue-white primary of magnitude 4.4 and a yellow secondary of magnitude 6.5.
Kruger 60 is an 11th-magnitude binary star consisting of two red dwarfs. The star system is one of the nearest, being only 13 light-years away from Earth.
NGC 7354 is a planetary nebula located in the constellation Cepheus
NGC 188 is an open cluster that has the distinction of being the closest open cluster to the north celestial pole, as well as one of the oldest-known open clusters.
NGC 7023 is a reflection nebula with an associated star cluster (Collinder 429); it has an overall magnitude of 7.7 and is 1,400 light-years from Earth. The nebula and cluster are located near Beta Cephei and T Cephei.
S 155, also known as the Cave Nebula, is a dim and very diffuse bright nebula within a larger nebula complex containing emission, reflection, and dark nebulosity.
^Ghisellini, G.; Ceca, R. Della; Volonteri, M.; Ghirlanda, G.; Tavecchi, F.; Foschini, L.; Tagliaferri, G.; Haardt, F.; Pareschi, G.; Grindlay, J. (2010). "Chasing the heaviest black holes in active galactic nuclei, the largest black hole". Monthly Notices of the Royal Astronomical Society. 405: 387. arXiv:0912.0001. Bibcode:2010MNRAS.405..387G. doi:10.1111/j.1365-2966.2010.16449.x. This paper does acknowledge the possibility of an optical illusion that would cause an overestimation of the mass.
^Weigelt, Gerd; Beckmann, Udo; Berger, Jean-Philippe; Bloecker, Thomas; Brewer, Michael K.; Hofmann, Karl-Heinz; Lacasse, Marc G.; Malanushenko, Victor; Millan-Gabet, Rafael; et al. (2003). "JHK-band spectro-interferometry of T Cep with the IOTA interferometer". SPIE. Interferometry for Optical Astronomy II. 4838: 181–184. Bibcode:2003SPIE.4838..181W. doi:10.1117/12.458659.
^"Smoky Shells". ESA/Hubble Picture of the Week. Retrieved 13 December 2012.