A rubber composition for a tire tread comprising: a diene rubber, silica, and a cured product; a content of the silica being from 20 to 100 parts by mass per 100 parts by mass of the diene rubber, a content of the cured product being from 0.3 to 30 parts by mass per 100 parts by mass of the diene rubber; the diene rubber containing a natural rubber and a modified butadiene rubber having a polyorganosiloxane group at a terminal, a content of the natural rubber in the diene rubber being from 30 to 90 mass%, a content of the modified butadiene rubber in the diene rubber being from 10 to 70 mass%; the cured product being a cured product obtained by curing a crosslinkable oligomer or polymer that is incompatible with the diene rubber, JIS A hardness of the cured product being from 3 to 45, wherein the JIS A hardness refers to the durometer hardness defined by JIS K 6253-3:2012 and the hardness is measured at a temperature of 25°C by a type A durometer; wherein the modified butadiene rubber has a conjugated diene-based polymer chain as a main chain and has a polyorganosiloxane group at a terminal of the main chain, wherein the conjugated diene-based polymer chain is a homopolymer chain of conjugated diene monomers; wherein the polyorganosiloxane group is a group bonded to the terminal of the main chain through a linking group formed from a divalent hydrocarbon group from 1 to 20 carbons which may have a substituent or through an ether group; a part of -CH 2 - of the linking group formed from a divalent hydrocarbon group from 1 to 20 carbons which may have a substituent may be replaced by -O-; wherein a silicon-containing linking group represented by General Formula (Si) below is present in between the linking group formed from a divalent hydrocarbon group from 1 to 20 carbons which may have a substituent; and the terminal of the main chain; ∗ 1-Q 1 -Si(R L1) 2 -A 1 -Si(R L2) 2 -Q 2 - ∗ 2... (Si) wherein, Q 1 and Q 2 are each independently a chemical single bond or -O-; R L1 and R L2 are each independently a substituent, and a plurality of R L1 and R L2 may be the same or different; A 1 is a chemical single bond, a polymethylene group having from 1 to 20 carbons ((CH 2) k (k is an integer from 1 to 20)), an arylene group having from 6 to 20 carbons, or a cycloalkylene group having from 5 to 20 carbons. ∗ 1 is a linkage position with ∗ 2 in another silicon-containing linking group or with the linking group formed from a divalent hydrocarbon group from 1 to 20 carbons which may have a substituent; and ∗ 2 is a linkage position with ∗ 1 in another silicon-containing linking group or with the terminal of the main chain. a content of the silica being from 20 to 100 parts by mass per 100 parts by mass of the diene rubber, a content of the cured product being from 0.3 to 30 parts by mass per 100 parts by mass of the diene rubber; the diene rubber containing a natural rubber and a modified butadiene rubber having a polyorganosiloxane group at a terminal, a content of the natural rubber in the diene rubber being from 30 to 90 mass%, a content of the modified butadiene rubber in the diene rubber being from 10 to 70 mass%; the cured product being a cured product obtained by curing a crosslinkable oligomer or polymer that is incompatible with the diene rubber, JIS A hardness of the cured product being from 3 to 45, wherein the JIS A hardness refers to the durometer hardness defined by JIS K 6253-3:2012 and the hardness is measured at a temperature of 25°C by a type A durometer; wherein the modified butadiene rubber has a conjugated diene-based polymer chain as a main chain and has a polyorganosiloxane group at a terminal of the main chain, wherein the conjugated diene-based polymer chain is a homopolymer chain of conjugated diene monomers; wherein the polyorganosiloxane group is a group bonded to the terminal of the main chain through a linking group formed from a divalent hydrocarbon group from 1 to 20 carbons which may have a substituent or through an ether group; a part of -CH 2 - of the linking group formed from a divalent hydrocarbon group from 1 to 20 carbons which may have a substituent may be replaced by -O-; wherein a silicon-containing linking group represented by General Formula (Si) below is present in between the linking group formed from a divalent hydrocarbon group from 1 to 20 carbons which may have a substituent; and the terminal of the main chain; ∗ 1-Q 1 -Si(R L1) 2 -A 1 -Si(R L2) 2 -Q 2 - ∗ 2... (Si) wherein, Q 1 and Q 2 are each independently a chemical single bond or -O-; R L1 and R L2 are each independently a substituent, and a plurality of R L1 and R L2 may be the same or different; A 1 is a chemical single bond, a polymethylene group having from 1 to 20 carbons ((CH 2) k (k is an integer from 1 to 20)), an arylene group having from 6 to 20 carbons, or a cycloalkylene group having from 5 to 20 carbons. ∗ 1 is a linkage position with ∗ 2 in another silicon-containing linking group or with the linking group formed from a divalent hydrocarbon group from 1 to 20 carbons which may have a substituent; and ∗ 2 is a linkage position with ∗ 1 in another silicon-containing linking group or with the terminal of the main chain.